Danfoss Randall - United Kingdom - News from Danfoss Randall

New All-In-One Programmable Room Stat With DHW Time Control

Sun, 29 Jun 2008 23:00:00 GMT

New All-In-One Programmable Room Stat With DHW Time Control

The new TP9000 Si from Danfoss Randall is a stylish ‘universal’ programmable room thermostat that incorporates an additional channel enabling the time control of domestic hot water. Factory-set to provide energy-saving chrono-proportional control as standard, the TP9000 Si allows selection of conventional On/Off control if required.

Operating on mains voltage (230Vac, 50Hz), this versatile control unit allows the user to select up to 6 different room temperature levels per day and to choose the exact times at which these changes are to occur. The domestic hot water time channel provides a programming choice of 1, 2 or 3 timing periods each day.

The TP9000 Si can be installer set to operate either in full 7-day, 5 day/2 day or 24-hour mode. These control options enable the heating system to be easily tailored to individual living patterns, thus only using heat when required and avoiding any unnecessary use of energy. But the TP9000 Si has even more to offer as shown below.

■ Time saving factory-set standard programmes – easily user-changed as desired.

■ Automatic summer/winter time change.

■ DHW only mode – summer operation.

■ Optional optimum start control feature.

■ Optional delay start control feature.

■ Optional remote room temperature sensor that can be mounted up to 50m from the controller provides extra flexibility in siting the control unit.

■ Temporary room-temperature overrides – up or down.

■ Selectable 1, 2 or 3 hour boost mode.

■ Frost protection and holiday modes for house protection when unoccupied.

■ Optional Service Interval timer function to remind of boiler servicing requirement.

■ Information button for quick viewing of next timed event.

■ Standard temperature setting range maximum (5 - 30°C) can be amended to 5 - 40°C at installation to help guard against hypothermia when required (e.g. in sheltered housing).The Danfoss Randall TP9000 Si is therefore a fully independent control for both heating and domestic hot water with numerous added features that make it an ideal all-in-one controller for modern central heating systems, optimising both energy-saving and home comfort.

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Best Ever Product Selection Guide From Danfoss

Sun, 18 May 2008 23:00:00 GMT

Best Ever Product Selection Guide From Danfoss

This year’s updated and improved Product Selection Guide (PSG) from Danfoss Randall is now available. It will be welcomed by all who rely on easily accessible and up-to-date information related to energy-saving heating and cooling controls.

The currently increasing demand for controls, coupled with continual new product introductions, is leaving many installers, specifiers and stockists in search of answers. Optimum energy-efficiency in buildings increasingly calls for the correct use of advanced, more-effective controls; and people lacking this understanding put their continued professional success at risk.

More than just a manufacturer’s product listing, this year’s PSG provides extra invaluable information to help people specify the right components. Beautifully illustrated, in full colour and easily navigable, it covers a comprehensive selection of essential domestic heating controls ranging from TRVs through conventional time controls and motorised valves to advanced programmable RF room thermostats and control packs. Matching lockshields are also featured. Full details of all the new Danfoss products – TP5000Si, TP4000, TP9000 Programmable Room Thermostats and the FlatStat Electronic Room Thermostat – have all been incorporated.

Commercial TRVs, time controls, pressure controls and multi-function thermostats are included together with details of underfloor heating products and applications.

Technical advice comes in the form of numerous wiring diagrams and system schematics, together with helpful controls selection guides. Building Regulation compliance assistance is provided in an easily-readable table that advises generic product solutions cross-referred to appropriate Danfoss controls. Information on underfloor heating applications is included. There is also a listing of Danfoss leaflet and data-sheets that may be photo-copied for easy and quick literature ordering.

All those whose work involves heating and cooling controls should be sure to obtain a copy of this latest Danfoss Randall PSG. Not to do so could leave a serious gap in their technical reference library and their ability to propose the best energy-saving solutions.

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	Request a PSG
	PSG online

75 Years Of Energy Saving

Tue, 13 May 2008 23:00:00 GMT

75 Years Of Energy Saving

Danfoss Randall Limited, one of the top three domestic heating controls manufacturers in the

, largely attributes its on-going success to the sound backing, technical skills and commercial philosophies of its parent company Danfoss A/S, currently celebrating the 75^th year of its establishment.

Established in 1933 in a farmhouse at Nordborg, southern

Denmark

, Danfoss A/S has grown into a global world-leader with manufacturing and sales organisations throughout the world. The Danfoss Group produces around 250,000 items per day from 61 factories in 25 countries. Core values on which Danfoss has always relied are:

■ Trust

■ Safe and reliable choice

■ Passion about technology

■ Global culture, local representation

■ Environmental and social responsibility

Danfoss invented the Thermostatic Radiator Valve (TRV) in 1943 and quickly became the world leader in sales of these controls, producing over half the world’s requirements. These and its many other products quickly established a reputation for top performance and reliability.

Danfoss Randall Limited was established at Bedford, UK, in 1992 by merging the Perivale-based Danfoss Building Services Group with Randall Electronics, the

’s leading time-control manufacturer. The company’s own special skills and technological know-how have since been combined with those of the parent group to develop ground-breaking products and ideas that are in use globally; products such as advanced programmers, programmable room thermostat and the energy-saving chrono-proportional control mode.

The Danfoss Group has already provided a very fruitful and beneficial 75 years for the world’s population. With its ever-constant core values and progressive subsidiaries like Danfoss Randall, it seems there is still much more to come.

Mains Operated Version Of TP5000 Si Introduced

Tue, 29 Apr 2008 23:00:00 GMT

Mains Operated Version Of TP5000 Si Introduced

Danfoss Randall has introduced a mains-operated (230V, 50Hz) version of its hugely popular and versatile TP5000 Si programmable room thermostat.

Incorporating all the outstanding features of its predecessors, this new TP5000M Si removes the need to periodically replace and dispose of dry-cell batteries, making it a slightly ‘greener’ solution. It is ideal for new-build properties with ready-installed power supplies or for replacing existing ‘accelerator-type’ room thermostats where supply cables are already in place.

The TP5000M Si is a simple-to-install-and-use 5-day/2-day programmable room thermostat that can be configured by the installer to provide 2, 4 or 6 events per day - or constant temperature control when required.

A big plus is the unit’s factory-set real-time clock with calendar function that eliminates any time-setting and BST/GMT time changes. Users do not have to alter the clock twice a year and installers need not set the time after unpacking the unit.

Chrono-proportional control modeis standard for the TP5000M Si. This fast-reacting, energy-saving control mode varies boiler on/off percentages to satisfy comfort requirements. Chrono-proportional cycling rates of 3, 6, 9 or 12 per hour can be selected. Conventional On/Off control mode is selectable by the installer.

The optional Service Interval function helps landlords comply with the annual boiler servicing requirements of Gas Safety Regulation 36. With this function operating, the unit provides audible and visual warnings from 28 days before servicing is due then reduces the heating output should the due date pass. More socially acceptable than switching off the heating altogether, this encourages tenants to allow access for servicing.

Other features of the TP5000M Si include:

-Large, easy-to-read LCD display.

-Built-in switching programme, easily changed by user to suit individual requirements.

- Programmable remote sensor inputs including remote room sensing, limit sensing for floor heating applications and tele-switch or window switch sensing.

- Selectable operating modes 5/2 day, 24 hour or A/B block programming.

- Selectable 6, 4 or 2 events per day.

- Fixed time, Delayed Start or Optimum Start start-up options.

- All user settings, including overrides, stored in non-volatile memory independent of battery state.

- Thermostat mode and frost protection.

Additionally, there are numerous simple push-button overrides that enable users to cope with temporarily changing heating needs.

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Home Heating Controls For The Low Carbon Economy

Wed, 16 Apr 2008 23:00:00 GMT

Home Heating Controls For The Low Carbon Economy

The need to constrict the consumption of carbon fuels, and the global-warming ‘greenhouse gases’ they produce, is ever more important to our society. Today’s media constantly bombards us with reports of ice caps melting faster than expected, warnings of wildlife extinctions, prophecies of catastrophic weather conditions and predictions of disastrous climatic changes. What should be done?

The UK government has issued a White Paper setting out projections for a low carbon economy, with carbon emissions into the atmosphere being reduced by 60% by the year 2050. Many other countries are equally concerned.

Home heating

In the UK, dwellings create around 27% of all emissions of carbon dioxide - the major part of this from home heating. Energy consumption in this sector clearly needs to be controlled.

Of course, we can all limit the use of energy in our homes simply by manually switching off the heating system when we feel the time is right. Unfortunately, few of us possess the self-discipline to maintain such a regime and, even if we did, likely results would be haphazard at least.

No! The solution is to use advanced automatic heating controls that maintain essential comfort levels while ensuring no energy is wasted at inappropriate times or at unnecessarily high temperatures.

Controls and Regulations

Domestic central heating in the UK really began around the middle of last century when a set of controls typically consisted of an electro-mechanical timer, a bi-metal room thermostat, a cylinder thermostat and, if you were lucky, a pump or motorised control valve.

Since then, all types of products – boilers, radiators, valves, pumps and controls – have evolved considerably, much aided by the advent of electronics.

A ‘minimum’ heating controls set now typically includes a full programmer allowing independent control of heating and hot water, a room thermostat, a cylinder ‘stat, TRVs, and a pump. Provision is required for an electric interlock that prevents the boiler firing if no demand for heat exists. Also, the latest Regulations call for separate zoning of living and sleeping areas.

Regulation of the way houses are heated has evolved through the mandatory requirements of the Building Regulations, Part L, Conservation of Fuel and Power, the latest version of which calls for high-efficiency condensing boilers in all new or refurbished dwellings that use ‘wet’ central heating systems.

All these requirements are easily met for new-build dwellings. Refurbishing older heating systems may not be so straightforward.

Refurbishment

Replacing existing boilers with new mandatory condensing types should theoretically produce a 10-14% improvement in system efficiency. However, depending on what temperature controls are fitted, this may not be the case.

The truth is that condensing boilers can only deliver peak performance while running in the condensing mode.

Many domestic room thermostats have comparatively slow response rates (i.e. some electro-mechanical types) that inhibit condensing from occurring for much of the boiler’s operating time. In fact, tests carried out have shown that such controls may only permit the condensing mode to cut in rarely.

Electronic room thermostats were shown to perform better, particularly those equipped with chrono-proportional control capability.

As opposed to the temperature-event based On/Off cycling of a traditional room thermostat, chrono-proportional control regulates the amount of time for which the boiler fires. In operation, each hour is split into sections (usually 3) and the controller calculates the proportion of these periods for which the boiler needs to fire to maintain desired comfort levels. This provides a closer control band and faster reaction to temperature change, resulting in improved energy savings and better home comfort.

The tests indicated that using On/Off electronic room thermostats, in place of electro-mechanical types, can produce reductions of over 2% in both energy cost and carbon emissions. Moreover, the use of chrono-proportional thermostats can push these savings up to 10%.

Consequently, when fitting a replacement boiler, checks should be made to confirm that any installed room temperature controls allow condensing to be achieved for most of the boiler’s operating time. If they do not, then ideally they should be replaced with either an appropriate electronic room thermostat or, for even greater savings, an even more versatile programmable room thermostat.

Do Your Thermostats Allow ‘Part L’ Boiler Performance?

Mon, 14 Apr 2008 23:00:00 GMT

Do Your Thermostats Allow ‘Part L’ Boiler Performance?

When householders need to replace existing central heating boilers with new ‘Part L’ mandatory condensing types they should rightfully expect improvements of 10-14% in system efficiency. However, depending on what temperature controls are fitted, they could be in for a shock disappointment.

The truth is that a condensing boiler can only deliver peak performance while running in the condensing mode. Without this, it performs the same as any conventional boiler. Boiler performance can be affected by associated controls. Many domestic room thermostats with comparatively slow response rates (i.e. some electro-mechanical types) inhibit condensing from occurring for much of the boiler’s operating time. In fact, in-house controlled tests carried out by Danfoss showed that this type of control permitted the condensing mode to cut in only rarely.

Electronic room thermostats seem to offer the solution, particularly those equipped with chrono-proportional control capability.

As opposed to the temperature-event based On/Off cycling of a traditional room thermostat, chrono-proportional control regulates the amount of time for which the boiler fires. In operation, each hour is split into sections (usually 3) and the controller calculates the proportion of these periods for which the boiler needs to fire to maintain desired comfort levels. This modulating control mode provides a closer control band and faster reaction to temperature change, resulting in improved energy savings and better home comfort.

Danfoss’ tests indicated that using On/Off electronic room thermostats, in place of electro-mechanical types, can produce reductions of over 2% in both energy cost and carbon emissions. However, the use of chrono-proportional thermostats can push these savings up to 10%.

Consequently, when fitting a replacement boiler, checks should be made to confirm that the installed room temperature controls allow condensing to be achieved for most of the boiler’s operating time. If they do not, then ideal solutions would be to replace them with either a new Danfoss FlatStat or, for even greater savings, a versatile Danfoss Randall TP5000 Si programmable room thermostat.

Chrono-Proportional Control Saves Energy

Thu, 10 Apr 2008 10:24:00 GMT

Chrono-Proportional Control Saves Energy

Tests carried out by Danfoss Randall explain why optimum performance from today’s mandatory high-efficiency condensing boilers can be difficult to achieve if existing heating controls are not updated. Chrono-proportional control, already incorporated into many Danfoss Randall thermostats, overcomes the problem.

The Danfoss tests, conducted in a custom-built, fully-controlled test house, confirm that room thermostats operating in chrono-proportional mode can provide a 10% reduction in energy consumption and carbon emissions compared to conventional mechanical devices. Chrono-proportional control divides hours into pre-settable fixed time intervals (typically 3 or 6 for radiator systems) and the quick-reacting thermostat calculates the duration of the ON period required to maintain desired comfort levels.

Full efficiency of a condensing boiler relies on it operating in the condensing mode. Slow re-acting mechanical thermostats can allow the system water to cool too much, requiring full circulation before the condensing cycle becomes functional. Under low loads this might not occur at all, resulting in ‘non-condensing’ type boiler performance.

Due to their control operation and faster re-action, chrono-proportional thermostats ensure boilers remains in condensing mode more often than with conventional On/Off operation, even at low heat loads.

Danfoss Randall TP5000Si and TP7000 programmable room thermostats, plus the RET-B range of thermostats all incorporate chrono-proportional technology.

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	TP5000 Si
	TP7000
	RET B

Chrono-Proportional Room Temperature Control

Sun, 09 Mar 2008 23:00:00 GMT

Chrono-Proportional Room Temperature Control

Chrono-Proportional room temperature control, currently incorporated into many of Danfoss Randall’s domestic temperature controls, is proving to be a certain method of achieving extra energy savings, reducing CO² emissions in homes and helping high-efficiency boilers attain peak performance.

As the name defines, chrono-proportional control is based upon regulating the amount of time for which the boiler fires instead of the temperature-event based On/Off cycling of a traditional room thermostat. In operation, each hour is split into sections (usually 3) and the controller calculates the proportion of these periods for which the boiler fires to maintain desired comfort level.

This modulating control mode provides a closer control band and faster reaction to temperature change resulting in improved energy savings and better home comfort.

Rapid thermostatic response is vital in enabling today’s mandatory high-efficiency boilers to maintain their condensing mode, by which they achieve peak performance. Chrono-proportional control easily enables this - but the slower reaction of many traditional On/Off thermostats can mean that boiler condensing mode is rarely achieved. Without being able to achieve condensing status these boilers cannot possibly achieve their SEDBUK ratings and deliver the energy-saving benefits expected.

Closely controlled in-house tests carried out by Danfoss Randall showed that if a property has only a simple mechanical thermostat installed, then the energy-saving benefits of a replacement high-efficiency condensing boiler will not be realised as the boiler will rarely be running in condensing mode. Switching to an on/off electronic room thermostat produces reductions of over 2% in both energy cost and carbon emissions.

However, the use of an electronic thermostat with chrono-proportional capability provides closer temperature control plus possible reductions of 10% in both fuel cost and carbon emissions.

The message, therefore, becomes very clear. When installers fit replacement boilers, they should ensure that the room temperature controls allow condensing mode to be achieved for most of the operating time. If they do not then an ideal solution would be to fit a chrono-proportional control unit such as the Danfoss Randall TP5000 Si programmable room thermostat, which is an advanced control suited to virtually all domestic applications.

Danfoss Room Thermostat Innovation

Sun, 10 Feb 2008 23:00:00 GMT

Danfoss Room Thermostat Innovation

An innovative thermostat from Danfoss Randall sets exciting new standards in room temperature control while offering outstanding aesthetics and ultimate ease of operation. The flush-mounting FMT230D electronic room thermostat, known in-house as the FlatStat, launches an unprecedented era of energy-saving in room temperature control.

The FlatStat is designed for mounting in standard one-gang, flush-mounted electrical accessory boxes. When fitted, most of the thermostat body is recessed neatly within the accessory box, blending almost imperceptibly with virtually any home décor and protruding only 16mm into the room. This feature alone, set against most of today’s visually obtrusive ‘block-on-the-wall’ thermostats, has obvious user appeal.

The unit’s user attraction does not stop there. A large central setting dial, an easy-to-read LCD display and two LEDs indicators for output and power status make the FlatStat thermostat stylish and superlatively easy to use.

Operationally, the FlatStat is way ahead of the market. As standard, it employs fast reacting chrono-proportional control, a time-based method proven to achieve considerable energy savings compared with conventional temperature-based On/Off thermostats. Chrono-proportional control also helps to ensure optimum performance from condensing boilers by allowing them to operate in condensing mode far longer. If required, traditional On/Off control mode can still be selected by means of a DIL switch.

Furthermore, another DIL switch enables easy selection of heating or cooling (for air conditioning, fan coils, etc.), making it suitable for a very wide range of applications.

The FlatStat is powered by a 230Vac, 50/60Hz supply. Its temperature setting range is 5° -30°C and its single SPDT output relay contacts are rated 10-264 Vac, 50/60 Hz, 3(1)A. Dimensions are 85 wide x 85 high x 35 deep and the unit has a maximum ambient temperature rating of 45°C. Easy range locking and limiting facilities are incorporated.

The Danfoss FlatStat room thermostat is a design breakthrough with the ability to increase energy savings, improve home décor and provide ultimate user simplicity.

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Control Valves In Variable Flow Chilled Water Systems

Fri, 01 Feb 2008 23:00:00 GMT

Control Valves In Variable Flow Chilled Water Systems

In building services, variable flow systems are essential as we strive for both energy efficiency and lifetime value for our clients. Cost savings on pumps and piping reductions mean the usage of these systems will continue to grow but they require care during the valve sizing process.

Control valves sizing is all too often described as an art. The reason for this is that, as hydronic systems have changed, the valve sizing calculations we make have also changed.

Variable flow systems require new calculations, new terminology and, most importantly, new technology. There is one definitive aim when sizing control valves – to find the perfect valve solution for your system. Finding that perfect valve involves understanding the hydronics of the project and recognising the importance of perfect control flow.

Control valve selection

The effects a variable flow system had on the selection of control valves, was not initially realised. A control valve was selected by using the same Kv calculation and the bypass on a 3-port valve blocked, giving a 2-port valve. Unfortunately it wasn’t that simple.

This is because our Kv calculation

Kv = Flow Rate (m³/h)

Δ P (Bar)

was based upon a constant pressure and a constant Kvs, delivering a constant flow. However, as areas of the variable flow system closed down the differential pressure increased, stepping up the delivery flow and causing overflow in the open circuits.

Overflow in a circuit is costly. Unfortunately, traditional control valves make it inevitable. As we size a control valve the Kv calculated almost certainly will not match the Kvs of the nearest appropriate valve. For example, a Kv calculation of 4.5 M3/h would most likely lead to selection of a valve with a 6.3 M3/h Kvs. This means the valve is capable of delivering 40% more flow than required. As pressure increases in our variable flow system our valve will deliver this extra pressure as flow.

This excess flow will cause the temperature to over-shoot the set-point. Once the room sensor has detected this overflow it will close the actuator, causing a sharp drop in flow. The process will repeat itself in a phenomenon described as ‘hunting’.

Hunting

‘Hunting’ causes the room temperature to constantly fluctuate, creating a major cost to clients in poor environment quality and increased maintenance. Over three-quarters of complaints to building managers are of a thermal sensation nature. These complaints are rarely due to inter-individual differences in preferred temperature but, instead, to increases as temperature deviation widens.

The solution that more than two-thirds of building managers use to answer this type of complaint is to change the set-point. By lowering the set-point by an average of 1℃ in a cooling system we increase its energy usage by up to 10%. The solution to the problems of ‘hunting’ and overflow in chilled water systems lies in the use of pressure independent control valves.

Pressure independent control valves

Traditional control valve sizing for constant flow systems involves a Kv calculation, actual pressure drop calculation and a check to ensure minimum valve authority is met. This method is complicated and inflexible, as the changes in design flow, circuit pressure, and required pressure drops can change the required valve, and reduce controllability. This method also relies on having the correct design information.

Pressure independent control valves such as the Danfoss AB-QM are used to limit the flow to the fan coil terminal and air handling unit. This flow is not affected by changes in inlet pressure. A diaphragm within the valve keeps the outlet pressure constant, and this delivers a constant flow to the terminal.

The added advantage of pressure independent control valves is that, when fitted with an actuator, they replace the manual balancing valve and motorized control valve with a single valve, thus reducing installation cost.

Danfoss AB-QM

Sizing of a Danfoss AB-QM combined flow-limiter and control valve is done purely on the flow. You first note the flow required to the coil, select a valve that can deliver a higher flow and set the required flow as a percentage of the maximum flow of the valve. This gives the exact design flow to the coil, and eliminates overflow. Changes in design pressures, and required flows can be easily accommodated. AB-QM valves can be set in seconds, without the use of tools.

The ABQM valve is available with or without test points; test points enabling flow verification for commissioning documentation and trouble shooting.

AB-QM valves are extremely compact and are available in 10mm-100mm sizes and handle flow rates from as low as 30 litres per hour to 41,000 litres per hour.

Control Valve Strategy

Pressure independent control valves can be used with any control strategy. The actuator options give a choice of thermic, 3-point control, or modulating control. This will work with building management systems and individual room controls, in the same way as traditional control valves. The actuators can also be used to set the valve by limiting flow. In 3-point control applications this can be done using a run time limitation. For example, for 70% design flow we give the actuator 70% of it’s total run time. With a modulating actuator, to achieve our 70% example we set the controller to control between 0-7v of the 0-10v signal.

Conclusion

Overflow affects the ability of the control system to achieve the set temperature. It need not be inevitable. Danfoss AB-QM pressure independent control valves enable fan coils and air handling units to have the maximum flow set exactly at design flow. Switching a traditional control valve to a pressure independent type should not be seen as only benefiting the mechanical contractor, by reducing installation cost. It benefits the systems integrator and most importantly the client, ensuring both improved comfort levels with reduced energy consumption.

Pressure independent control valves are an essential part of the hydronic control in chilled water applications. They are simple to select and easy to set. They enable a steady pressure, a steady flow and most importantly a steady room temperature.

Quality, Room-Enhancing Comfort Controls For Bathrooms

Thu, 15 Nov 2007 10:38:00 GMT

Quality, Room-Enhancing Comfort Controls For Bathrooms

The appeal of an otherwise beautiful and expensive new bathroom can be spoiled by a touch of scruffy plumbing and the use of heating controls that do not match your smart radiators and towel rails. Attention to such detail makes all the difference.

Danfoss Randall’s RAS-D² and RAS-C² radiator thermostats (TRVs) provide first-class solutions. Also, Danfoss matching high-quality lockshields and other stylish components are available to improve often-neglected aspects of bathroom aesthetics.

Top-of-the range RAS-D²radiator thermostats come with chrome-plated, brass valve bodies and a choice of sensors either in subtle white with chrome styling or in stunning all-chrome. This latter finish, in particular, compliments many of the latest designer radiators and towel rails.

All valve bodies for these controls are reversible and bi-directional, incorporating the Danfoss patented ‘Revolver’ flow-selectable feature to ensure trouble-free installation without any risk of water hammer. In angle and straight patterns, they have a ½” BSP (R½”) tail piece connection to the radiator and include 8mm, 10mm and 15mm compression fittings to connect the valve to the pipework.

Room temperature is controllable between 8°C – 28°C and the sensor head carries ‘Frost Protection’ and ‘Positive Off’ setting positions. Convenient combi packs containing sensor, valve body and lockshields are available.

The Danfoss Randall RAS-C² radiator thermostat has a stylish white sensor head and will impart a quality feel to many modern bathrooms. Many of the features of this control are the same as those of the RAS-D², offering the same setting range, Revolver flow selectable device, Positive Off and Frost Protection settings, etc., with 8/10 and 15mm valve sizes in angle and straight versions. Sensor mounting requires no tools; it just needs to be pressed onto the valve body and its clamping ring tightened by hand.

RLV-D lockshield valves are manufactured to extremely high standards and finished to match the Danfoss range of radiator thermostat valves. They are available in 8/10 and 15mm angle pattern as well as a version incorporating a 10mm push-fit elbow.

An accessory pack to convert the valve into a conventional wheelhead valve is also available.

Apart from these mainstream controls, Danfoss Randall also offers a specialised range of TRVs intended for designer radiators and towel rails in bathrooms. This RA-URX luxury range is available in white or chrome, and has an innovative self-sealing valve-to-radiator connection that enables seamless, elegant and easy installation. Its compact design allows the sensor to be mounted beneath the towel rail, parallel with the wall, thus reducing the risk of accidental knocking and damage.

The RAX radiator thermostat is a room sensor developed for controlling bathroom temperatures where the towel rail is the primary source of heating.

The RTX return temperature limiter, which monitors return temperature, is ideal where the towel rail is the secondary source of heating and keeping the towel rail warm, irrespective of room temperature, is a priority.

The VHS valve integrates the functions of radiator thermostat, lockshield valve and connection system into one compact, easy-to-install unit. With versions incorporating bottom or back connections, these valves can be used together with RAS-C² or RAS-D² sensors. There is also a snap-on cover to enhance their aesthetics.

New Controls Website Has The Answers

Mon, 25 Jun 2007 13:36:00 GMT

New Controls Website Has The Answers

How can specifiers and installers choose the correct controls for each installation? The answer is to obtain help and advice from Danfoss Randall’s new website.

Today’s high demand for energy-saving controls, plus the continual introduction of new products, has left many installers searching for answers. Optimum energy-efficiency in buildings increasingly calls for the use of advanced, more-effective controls. Yet some installers remain unaware of the latest, ground-breaking products that are essential to their continued professional success. Where can they find the information they need?

Danfoss Randall’s totally revised website, www.danfoss-randall.co.uk, is an excellent starting place. Many months of research, dedicated work, structured thought, imagination and unswerving attention to detail has created an easily navigable on-line encyclopaedia of clear and easily accessible information on controls for domestic, commercial and industrial heating/cooling applications. Visitors to the site will also find valuable advice, tips and detailed connection diagrams.

Although structured around Danfoss products, the information and advice provided relates easily to controls generally. Information can be found about the following types of controls.

■ Commercial and domestic radiator thermostats (TRVs), sensors and lockshields.

■ Time controls, electronic and electro-mechanical – a comprehensive selection from domestic timeswitches through advanced programmers to sophisticated commercial units.

■ Electric and electronic thermostats – an extensive variety of heating, heat/cool, programmable, dial-setting, cylinder, pipe, frost, hot water and immersion types.

■ Underfloor heating – controls and pipe fittings for water based systems, electric floor warming mats.

■ Balancing valves - automatic and manual.

■ Motorised valves and other controls – domestic shoe and paddle types, commercial control valves and actuators, automatic by-pass valves.

Navigation of the website is extremely quick and easy, and is helped by its cool, uncluttered style. With just a few clicks, product listings, selection tables and illustrations appear on screen instantly. Favourite products can be conveniently saved as a list for future visits.

Data sheets, Instructions and User Guides may be downloaded in pdf format and printed. Clear wiring connection diagrams for all popular controls are provided.

An advice section entitled ’Understanding Heating Controls’, which explains controls usage and explodes many of the myths that have grown up surrounding domestic heating controls, is likely to be of major interest to all. This section can be easily downloaded and printed.

Full contact details are given to enable site visitors to obtain Sales Office support, order literature, obtain details of Training Seminars and pose specific controls problems to a Danfoss expert. The site is indeed a comprehensive source of user support.

The Home page states, ‘At Danfoss we are dedicated and focussed on developing control solutions that facilitate architects, consultants and system integrators to create modern commercial and residential buildings that fulfil the highest standards for optimum indoor climate. We make people comfortable!’

This also applies to the way Danfoss Randall’s new website is constructed. Visitors to it can be certain of an easy, comfortable search for the information they require.

UK’S First RF ‘Setting Dial’ Room Thermostats

Wed, 25 Apr 2007 14:18:00 GMT

UK’S First RF ‘Setting Dial’ Room Thermostats

Danfoss Randall’s exceptionally stylish RET B(RF) range marks the arrival of the UK’s first RF (wireless) analogue room thermostats, bringing a huge sigh of relief from users and installers alike. Simple analogue setting dials remain the preferred method of setting and adjusting room thermostats in most households.

This instant user appeal, coupled with their quick, hassle-free fitting and many features not found on other room thermostats, makes RET B(RF) thermostats the automatic choice for both new-build installations and system upgrades. Ideal and easy-to-use for most basic domestic duties, they also provide additional options and features to improve home energy efficiency.

RET B(RF) thermostats operate by transmitting secure unique radio signals to hard-wired RX receiver/switching units placed adjacent to the boiler or other controls system components. This eliminates the need for long cable runs, thus overcoming any associated household disruption and making-good whilst dramatically reducing installation times.

The thermostatic units themselves, battery powered and requiring no external power supply, can be simply wall-mounted in any appropriate temperature-sensing location, either as replacements for conventional electro-mechanical two-wire units or as new controls. They can be sited up to 30m away from their receivers.

Every RET B(RF) model utilises a micro-processor that, in addition to providing accurate room temperature control, also drives an easily-read liquid crystal display (LCD) showing actual room temperature in either Centigrade or Fahrenheit during normal operation. This display changes momentarily to indicate set temperature whenever the setting dial is rotated. The LCD is also used to display output relay and battery level status.

RET B (RF) thermostats allow the choice of On/Off or chrono-proportional control modes for heating or cooling plus the selection of compressor delay timing when cooling is selected. All models have a setting range of 5° - 30°C and a switching differential of ±1°C. They are powered by 2 x AA/MN1500 alkaline batteries.

Apart from the basic model the following specialist versions have been added to the range.

RET B-LS (RF) – Thermostat with analogue setting and LCD, plus a manual Auto/Off switch to turn off the thermostat output during periods when its operation is not required. The Off selection is clearly shown in the LCD.

RET B-NSB (RF) – Thermostat with analogue setting and LCD, plus a manual Day/Night switch that, when set to Day, controls at the set temperature. When Night is selected, control is 4°C lower than the set temperature.

RX receiver units are available as single channel, two-channel and thee-channel versions.

Electric Underfloor Warming From Danfoss

Wed, 25 Apr 2007 14:15:00 GMT

Electric Underfloor Warming From Danfoss

In the rapidly growing UK underfloor heating sector, it is good for installers to be able to turn to quality products. Products that have been developed and have proven reliability in areas of continental Europe where this form of heating has been widely used for decades. Danfoss underfloor warming products, for electric systems, can be installed in the safe knowledge that they cannot be surpassed for quality or dependability.

One of the simplest ways of providing electric underfloor heating is to lay Devimat™, a thin electrically heated mat designed for installation within an adhesive layer under tiled, wooden laminate and even asphalt/bitumen floors. Easily installed by anyone capable of following the simple instructions, it can be laid on top of the existing floor, raising floor height by a mere 3.5 mm.

To prevent overheating, a Devimat™ system is controlled by a floor temperature sensor and wall mounted electronic Devireg™ thermostat. Devimat™ is guaranteed for 10 years.

Hydronic Floor Heating

Danfoss also provides a wide variety of quality controls for piped under floor heating systems. This product range includes thermal actuators for controlling manifolds, return temperature limiters, self-acting room temperature control valves, a range of small seated valves and an 8 zone wiring centre for use in systems having hard-wired room thermostats.

Part P And Domestic Heating Controls

Wed, 25 Apr 2007 14:13:00 GMT

Part P And Domestic Heating Controls

New Building Regulations, Part P, Electrical Safety, took effect in January 2005, and were introduced to increase the safety of households by improving the design, installation, inspection and testing of electrical installations in dwellings when these installations are being newly built, extended or altered. They set mandatory requirements for electrical installations, or changes to electrical wiring.

All new fixed electrical installations or changes to existing wiring in English and Welsh dwellings, possibly including the fitting of electric controls, must now either be self-certified as compliant by competent and approved electricians, or notified to the local building control officer prior to commencement for inspection and approval. This applies especially to electrical work carried out in kitchens and bathrooms.

Scope of Part P

Part P applies to all fixed installations beyond the supplier’s meter in buildings or parts of buildings including:

Dwellings
Combined dwellings and business premises with a common supply (shops, pubs, etc.)
Common access areas in blocks of flats (not lifts)
Shared amenities in blocks of flats (laundries, gymnasiums, etc.)
Outbuildings. Including sheds, garages and greenhouses.
Garden lighting and power supplies

It covers alterations and additions to existing installations (including rewires), as well as to new construction, but not the inspection and testing of existing electrical installations. However, any remedial work carried out to correct deficiencies in a Periodic Inspection Report (PIR) falls within the scope of Part P.

Notification

All proposed electrical installation work in dwellings needs to be notified to a building control body before work commences, unless:

The proposed work is to be undertaken by a prescribed competent person (an individual or a firm) authorised to self-certify compliance on completion of the work, or
The proposed work is minor, and it is not in a kitchen or in an area classified as a special installation or location

Competent Firms

For the purposes of Part P, ‘Competent Firms’ are those registered with Government-approved self-certification schemes such as NICEIC, BREC, BSI, ELECSA and NAPIT.

Special installations or locations

These include: -

Locations containing a bath tub or shower basin
Swimming pools or paddling pools
Hot air saunas
Garden lighting or power installations
Solar photovoltaic power supply systems
Electric floor or ceiling heating systems
Extra low voltage lighting installations
Other than pre-assembled, CE- marked lighting sets
Small scale generators such as microCHP units

All electrical installation work in such areas (as well as in kitchens) needs to be notified, or self-certified by a prescribed competent person, even if only ‘minor works’.

Minor work

Minor work is electrical work not involving the addition of a new circuit, such as the addition of socket outlets or lighting points to existing circuits and the replacement of accessories.

Other Responsibilities

Contractors self-certifying compliance with Part P will also have to certify compliance with other relevant parts of the Building Regulations that have been affected by the electrical work, such as Part B (fire safety), Part F, Part M (accessibility) and Part L1 (energy conservation).

Enforcement

Failure to comply with the requirement is a criminal offence. Local authorities have the power to require the removal or alteration of work that does not comply.

Industry Reaction

Wide consultation has taken place on all these measures but trade reaction remains mixed, with many installers questioning whether there is ample justification for the disruption and additional costs that might result. Not everyone is opposed and some take the view that such legislation has to be good for the industry in the long term, giving it a higher standing and better reputation.

Some manufacturers agree there is confusion in the workplace and uncertainty about the level of training they should be offering installers.

There really can only be one way forward and the Government has already made the decision. Manufacturers, specifiers and installers are all required to do their jobs properly. A safe and energy efficient nation surely is the target and we have the controls and technology to carry it through.

Part P has certainly been a source of confusion but, with goodwill and co-operation, we can all work to overcome difficulties found in the written word.

Danfoss Randall Launches Service Interval Time Controls

Wed, 25 Apr 2007 13:50:00 GMT

Danfoss Randall Launches Service Interval Time Controls

Danfoss Randall Limited has launched three ground-breaking ‘Service Interval’ central heating time controls. Based on the popular and well-proven Mk18 range, these new controls incorporate extra features that will benefit all users whilst the socially-conscious Service Interval function will appeal directly to Housing Associations, Local Authorities, private landlords and developer/specifiers.

Gas Regulation 36, part of the Gas Safety (Installation and Use) Regulations 1994, requires landlords to ensure that all domestic heating boilers in their premises are checked and serviced every year.

But how can they have boilers serviced if they cannot gain access to them?

Many tenants are simply not interested in co-operating, especially if it means losing a day’s earnings in the process. Consequently, landlords can face weeks of frustration and horrendous costs to cover police attendance, making good, etc., should they need to gain entry forcibly.

Current solutions aimed at ‘encouraging’ tenants to provide access include timers that shut down heating systems completely when annual services become overdue. During cold spells, this can create risks of hypothermia among elderly, infirm and very young residents plus possible damage to premises, pipework and furnishings. Non-compliance with Gas Safety Regulation 36 might then become the landlord’s least concern.

Danfoss Randall’s new Service Interval time controls offer a far more socially responsible solution. They do not shut down the heating system completely but provide the compromise of significantly reduced heat output until the boiler is serviced.

Initially, a Service Company Engineer will set the Service Interval – any time from 28 days to 24 months - into the control unit. Then, 28 days prior to the service date, at 12 noon, a buzzer will sound for ten seconds and the unit’s display will start to alternate between SER – TIME every 2/3 seconds. The buzzer will sound each following day at 12 noon either until the boiler has been serviced and the unit reset or the service date has passed.

After the service date has passed, at 12 noon the internal buzzer will sound continuously until reset by the occupier. This will repeat every 24 hours. Central heating and domestic hot water outputs will then be restricted, operating for just the first 15 minutes of every hour of their programmes. All overrides and programming buttons will be disabled and button functions confined to audible alarm cancellation only until the service has been completed and the unit reset by the authorised service engineer.

An important innovation for all users of the new Danfoss Randall service interval controls is that they incorporate factory preset Calendar Clocks, thus eliminating the need to initially set time and day details and to make bi-annual BST/GMT adjustments. These are, therefore, truly set-and-forget controls. They also provide all the proven features of the Mk18 range, including the Holiday programme.

Versions available are: -

TS715 Si Electronic single channel timeswitch with service interval timer, 7 day, 5/2 day or 24 hour. Backlit LCD display and voltage-free output contacts.

CP715 Si Electronic common time-base programmer with service interval timer, 7 day, 5/2 day or 24 hour. Backlit LCD display.

FP715 Si Electronic fully-independent time-base programmer with service interval timer, 7 day, 5/2 day or 24 hour. Backlit LCD display. Fully featured.

Easy-To-Use Sophistication From Danfoss

Wed, 25 Apr 2007 13:48:00 GMT

Easy-To-Use Sophistication From Danfoss

Product sophistication can only succeed if it comes with operational simplicity. Because of today’s requirements for improved energy-efficiency in the home, the latest domestic heating controls need to offer increased sophistication and flexibility. Happily, the best of these advanced products are as easy to use as their forerunners.

Part L of the Building Regulations now requires the fitting of high-efficiency boilers. In many installations, these boilers can only achieve optimum performance if their associated controls provide adequate versatility and, perhaps, additional user features.

Not only this, discerning users have recognised that upgrading their heating systems to allow them to tailor performance closely to their household routines can reduce costs and significantly improve comfort. Installers need to make sure the upgraded systems are easy to operate.

Easy-to-use

To ensure their products are totally user-friendly, manufacturers require huge understanding of applications and technologies, in-depth recognition of user needs plus the ability to turn all this input into design solutions. End users, therefore, would be best advised to source controls from long-established successful companies.

No controls manufacturer has more application experience, product know-how and design resources than Danfoss.

Established over 70 years ago, Danfoss has grown into a global controls giant able to call upon application experience from every corner of the world. Commanding unsurpassed R & D and test facilities, and employing the finest engineers from every relevant technology, Danfoss produces finest quality controls designed with the end user firmly in mind.

Programmable room thermostats

Probably the most important advanced domestic heating control introduced over the past few years is the programmable room thermostat. These devices combine the temperature control function of a room thermostat with the timing function of a programmer, allowing users to easily and quickly programme a number of automatic daily room temperature changes to match regular household activities. Thus, a dwelling’s central heating system will operate only at the varying levels and times needed, saving considerable energy compared with using a conventional ‘one-temperature’ room thermostat. Home comfort levels improve because overheating is prevented.

Latest models

Danfoss Randall offers a number of programmable room thermostat options including:

TP5000. An extremely stylish, simple-to-install battery-powered 5/2 day programmable room thermostat providing the flexibility of up to six time-and-temperature changes each day with different programmes for weekdays and weekends. If required, it can be set for just two events each day. Programming is simple and intuitive.

Offering the choice of either on/off or chrono-proportional control, the TP5000’s many useful user features include frost protection mode, thermostat mode, time or temperature display option and programme overrides. It is ideally suited to combination boiler systems.

TP7000. This control offers even more sophistication. It provides true 7-day as well as 5/2 day programming, with the choice of either hard-wired battery or mains powered models.

All user features from the TP5000 are incorporated plus extras such as a positive Off setting, extend function (1, 2 or 3 hours), 99-day holiday function and optimum start control. Remote sensing versions are available.

Wireless (RF) Controls

RF thermostats transmit control signals by unique, secure radio waves. This can be an important feature, particularly for upgrade work.

Fitting RF controls overcomes the disruption (lifting carpets and floorboards, drilling walls, damaging décor, etc.) that would otherwise be necessary in running new wiring. This means easier, quicker installations with lower costs and less upheaval for the householder.

RF versions of both the Danfoss Randall TP5000 and TP7000 programmable room are available.

The wall-mounted thermostats transmit secure digital control signals to RX receivers fitted within 30 metres. These receivers are sited near and hard-wired to either boiler or other control component. Receivers can be 1, 2 or 3 channels, which is ideal for zoning applications.

Existing controls

Not only brand new controls are ‘advanced’. Under Danfoss’ policy of continual product improvement, existing controls are developed either functionally or constructionally to provide improved durability, dependability, styling or cost reductions.

Notable examples are Danfoss 2-port motorised valves, both shoe and paddle types, the designs of which have been refined from basic concepts to improve their robustness and durability. The RMT range of room thermostats has also seen similar improvements.

Fine-tuned to market needs

Because of Danfoss’ years of experience, its global network, know-how and technical expertise, the company remains fine-tuned to market needs at all times. In this way, it has succeeded in matching sophistication to simplicity and in providing the most relevant quality controls for virtually all applications. There is no better provider of easy-to-use sophistication for improving home efficiency.

Automatic Flow Limiter And Control Valve In One

Wed, 25 Apr 2007 13:41:00 GMT

Automatic Flow Limiter And Control Valve In One

A new-generation control valve from Danfoss has become today’s obvious choice for balancing and controlling heating and cooling units such as fan-coils, chilled ceilings and air handling units.

The unique new Danfoss AB-QM is an extremely compact dual-purpose valve that can be used as an automatic flow limiter or, when fitted with an actuator, as a combined flow limiter and temperature control valve. It is perfectly suited to the high demands of modern heating and cooling systems.

When the AB-QM is employed just as an automatic flow limiter, the user simply needs to turn the presetting scale to the desired flow rate – a simple set-and-forget procedure. A built-in diaphragm then maintains a constant low differential pressure across the valve’s setting cone to ensure the maximum set flow is not exceeded.

Fitting the AB-QM with one of four Danfoss thermal-wax or electric actuators upgrades the unit to a single control valve fully capable of providing both temperature control and automatic flow balancing. Control is perfect because a diaphragm creates a pressure-independent zone inside the valve, automatically ensuring that the flow cannot be influenced by other factors. Constant low differential pressure across the setting cone enables the use of small actuators that require only low closing force.

The compact design of the AB-QM makes it easy to install in areas of limited space. Installation costs are further reduced because only one valve is needed instead of two. A shut-off facility is incorporated for easy maintenance.

The AB-QM can be supplied in versions fitted with test nipples, and this makes it the first automatic flow limiter enabling flow to be directly metered with equipment such as the Danfoss PFM 3000, which measures flow, differential pressure and temperature in heating and cooling systems. This facilitates verification and documentation for when projects are handed over and also helps in trouble shooting.

Danfoss AB-QM valves are available in 10, 15, 20, 25 and 32 mm sizes with or without test plugs. They can handle flow rates from 30 – 3200 litres per hour.