How They Work
In the outdoor unit the refrigerant meets the outdoor air in the evaporator (heat exchanger). The air is drawn through the evaporator by a fan located on side of the Air Source Heat Pump. The refrigerant, which is in a liquid state absorbs free energy from the air and evaporates in this process. A sensor in the expansion valve ensures that the liquid refrigerant collects the correct amount of the ‘free energy’ before the refrigerant (now in a gas state) is led into the compressor. The compressor increases the pressure of the refrigerant. The temperature of the vapour reaches approximately 100°C. The warm gas is then led into the condenser. The condenser is the heat pump’s heat emitting part. In the condenser, which is a fully brazed heat exchanger in stainless steel, the refrigerant (gas state) meets the water from the heating system (radiators and/or floor coils). When the warm gas is cooled by the circulating heating water, it condenses into a liquid state.
Energy is emitted in this process to the heating system or the hot water. After the condenser, the refrigerant, which is now in liquid form, continues through a drying filter. The drying filter is used to collect any moisture in the system. After the filter it continues on to an expansion valve. The refrigerant pressure is lowered in the expansion valve. This also causes the temperature to drop. When the refrigerant has left the valve and passes the evaporator it changes to vapour again. This completes the refrigerant circuit. The expansion valve is equipped with a sensor (bulb) just before the compressor. The sensor controls the amount of fluid entering the evaporator.
Air Source Heat Pumps – Applications
Air source heat pumps do not incur any ground works cost for the installation and laying of pipe. The cost of ground works can be significant for ground source heat pumps. Air Source Heat Pumps provide a low cost solution for space heating and hot water. Return on investment against oil and LPG heating systems can take as little as five years. Residential Dwellings
Air Source Heat Pumps – Anything Else?
Air source heat pumps have no major parts outside exposed to the elements, the organ’s compressor and circulation pumps are all internal. The intake fan is the only feature which is external and kept at optimum working temperature with the support of an internal defrost cycle system ensuring operation in all seasons. The internal defrost system uses the hot water collected by the air source heat pump as opposed to direct electric. Air source heat pumps should last for over 25 years with low maintenance requirements.
For more information about Air Source Heat Pumps and their installation and our range of Heat Pumps contact us on 03335 772 544 to speak to one of our team or complete the enquiry form on the website.