An air-to-water heat pump transfers heat from outside air to water,
thereby heating your radiator or floor heating. It can also heat water stored
in a thermos for use in hot water taps, showers and bathtubs.
The working principle of the heat pump:
The heat pump controls the temperature by transferring heat. The heat
pump consists of three basic components: outdoor unit (evaporator), indoor unit
(condenser) and refrigerant. The refrigerant transfers heat as it circulates
between the outdoor unit and the indoor unit.
1. The evaporator extracts energy from renewable energy sources (air,
water, geothermal or solar energy) by forcing liquid to be converted into gas.
2. The compressor compresses the gas, thereby increasing its
3. The condenser exchanges the heat from the gas to the heating system
to restore the gas to a liquid state.
4. The expansion valve reduces the pressure of the refrigerant, which
triggers evaporation and the cycle restarts.
Benefits of heat pump:
1. The installation planning of air-water pumps is easier because they
are smaller and do not take up much space. However, their energy efficiency is
twice that of huge oil or gas systems. With this high efficiency, you can
significantly reduce water and electricity bills, and the additional income
that RHI brings, you can save even more.
2. As the air-water heat pump uses air to generate energy, the operating
system is simple and risk-free.
3. The air source heat pump of suitable size and good quality can save
you electricity, and the heating cost is low, but it will not affect the heat
output and comfort.
4. Air source heat pumps dominate the renovation market, but they are
also very suitable for new construction.
Disadvantages of heat pumps:
1. There is a risk of low efficiency when air source heat pumps operate
in very cold weather conditions, so it is very important to check the seasonal
coefficient of performance (SCOP) to understand the annual average performance.
2. If you are considering investing in air-to-water devices because they
are compact and easy to maintain, please consider the noise level before
placing the internal device in a place other than the utility room.
3. Another planning consideration is the cost of good insulation,
because this will have the greatest impact on your future savings by using
air-to-water heat pumps.
4. Finally, depending on the condition of your existing radiator or
floor heating system, you may need to pay for replacement, which will
significantly increase installation costs.
Types of air-to-water heat pumps:
The system consists of an outdoor heat pump, which is directly connected
to an internal hot water tank through a water pipe. The water is then
distributed from the water tank to the hot water and heating circuit according
to any conventional system.
2. Split type:
The system incorporates an outdoor heat pump, which is connected to a
heat exchanger located inside through a refrigerant pipe; then it is connected
to the hot water tank in the same way.
Is air suitable for water heat pumps?
To judge whether the air source heat pump is right for you, you need to
consider several key issues:
1. Do you have a place to put it?
• You need a place outside your
home where you can install the device on a wall or on the ground. It needs
enough space to get good air flow. Sunny walls are ideal.
2. Is your house soundproof?
• Since the air source heat pump
works best when it generates heat at a lower temperature than traditional
boilers, your house must have good heat insulation and wind resistance for the
heating system to function.
3. What fuel do you want to change?
• If the system is replacing
electricity or coal heating systems, it will pay for itself more quickly. For
households that use main gas, a heat pump may not be the best choice.
4. What type of heating system will you use?
• Due to the need for lower water
temperature, the performance of air source heat pumps in underfloor heating
systems or warm air heating systems is better than that of radiator-based
5. Is the system intended for new development?
• Combining installation with other
construction work can reduce the cost of installing the system.
The cost of air-to-water heat pumps:
The cost of installing a typical system is approximately £6,000 to
£12,000, depending on the size of the property. Operating costs will depend on
many factors, including the size of your home, the degree of insulation, and
the room temperature you want to achieve.
The cost of using air to water heat pump:
1. Your heat distribution system.
• If you have the opportunity,
floor heating is more effective than radiators because the water does not need
to be as hot. If floor heating is not possible, use the largest radiator
possible. Your installer should be able to advise on this.
2. Your fuel cost.
• You still need to use the heat
pump to pay for fuel because it is powered by electricity, but you can save the
fuel that is being replaced.
3. Your old heating system.
• If your old heating system is
inefficient, you are more likely to see lower operating costs for the new heat
4. Water heating.
• If the heat pump provides hot
water, it may limit the overall efficiency. You may want to consider using
solar heating to provide hot water in the summer and help improve the
efficiency of the heat pump.