Why our air source heat pumps

Technical know how
Over 25 years we have built up a wealth of knowledge on energy efficient heating systems.  We know how to correctly size a heat pump in order to give the right amount of heat for any building, throughout the year.  We know how to make a heat pump work with any type of heating system.  And we know how to link a heat pump in with other heating plant for complete system integration schemes.

Right for our climate
Radiant Heating Solutions Ltd has designed a range of heat only air source heat pumps suited for the UK climate.  Made for Radiant by Dismy Environmental Products, these heat pumps use the very latest refrigeration technologies.  They work effectively in temperatures as low as -7 degrees C.  We even have units that can be specified to work in temperatures as low as -20 degrees C.

Large range
Our single phase units have output ranges from 5KW to 11KW with single compressors and 14KW to 24KW with twin compressors.  Our 3 phase units range from 14KW to 55KW.  All of them can do heating and hot water and they can also be specified to do cooling if required.

We also have a range of direct heat swimming pool heat pumps.  With outputs from 3KW to 25KW. These clever heat pumps are fitted directly into the filtration circuit of the swimming pool.

What you get at a glance
All our heat pumps use scroll compressors, R407c (or R410a) refrigerant gas, 316 grade stainless steel heat exchangers and micro-processor controls.  We also fit auxiliary heaters to boost the performance in very cold weather and tray heaters to assist in clearing water in the defrost cycle.  We also fit as standard the water circulation pump.  Our heat pumps are easy to install by plumbers, electricians and any competent DIY person.

It is very important to size the heat pump correctly for the job it is going to do.  In our comprehensive range will be the correct sized unit for your project.  The outputs from our machines are based on an air temperature of 2 degrees C and a heated water flow of 35 degrees C.  This is the European standard measurement for heat pumps and will normally be displayed as A2/W35.  When comparing different heat pumps it is important the make sure that the stated output always relates to this standard.

The performance of a heat pump is referred to as the co-efficiency of performance (COP).  This in simple terms is the relationship to the amount of energy used to the amount generated.  If the heat pump uses 1KW of electricity and produces 3KW of heating water the COP would be 3.
The performance of an air source heat pump will vary according to the outside temperature and the heating water temperature.  To learn more please go to our how to specify air source heat pumps page.

Heat only heat pumps

Heat only heat pumps



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When the air temperature is around 5oC and lower there is sufficient moisture to ice up the evaporator. This build up of ice will impair the performance of the heat pump and must therefore be removed. This is automatically done by the internal controls of the heat pump by reversing the refrigerant gas circuit.
The output of the heat pump is only heated water. Most heat pumps can be ordered as a heat and cool configuration when a cooling option is required. Dedicated heat only heat pumps have a higher performance in heating mode than a similar heat/cool unit.
When an ASHP defrosts the melt water could freeze around the bottom of the evaporator.  To prevent this a low grade heating element is fitted around the sump or tray of the evaporator.  This element can be an electric trace heater or the warm part of the gas circuit pipe work.
These are typically electric elements rather like an immersion heater that will be switched on to boost the output. These are very common in ASHP installations and also in some GSHP installations. They will either be fitted in the heat pump cabinet or alternatively in the buffer tank.