Heat Pumps 101

When you need heat to be transferred from one area to another, you cannot simply pick it up and move it. Yet the need is still there. That is what heat pumps were created for. The electrical installation transfers heat energy from one area to another. Its function can be switched between cooling an area, such as an air conditioner or refrigerator, to heating up a controlled space. Ultimately, heat pumps are used to manipulate the temperature of a controlled space.

How do heat pumps work?

Based on compressor mechanics, and a cyclic movement, heat pumps transfer energy. A substance called ‘refrigerant’ is transferred through a cycle of evaporation and condensation, thereby transferring heat. The refrigerant is pumped through two heat exchanging coils via a compressor.

Heat is extracted from the surrounding air and causes the refrigerant to heat up. In the first coil, a low pressure causes the refrigerant to evaporate and the heat to be absorbed in the surroundings.

In the second coil, the refrigerant is compressed at a high temperature, causing further heat and condensation to occur. At this point, the heat that was earlier absorbed during the evaporation process, is released.

The heat pump cycle is fully reversible, thereby allowing the mechanism to have either a cooling or heating effect – whatever is desired.

The basic water heat pump cycle

The domestic heat pump can be used as an energy-efficient way to heat water. The process is as follows: 

1. Fan – a fan is used to pass the ambient air over the evaporator which boils the refrigerant to evaporative at a low temperature.
2. Vapor – the temperature and pressure of the vapor is increased as it passes through the electric compressor
3. Warm vapor – heat (for a water of heating system) is produced as the warm, high pressure vapor enters the heat exchanger
4. Condensed vapor – The condensed vapor passes through the expansion valve, where the temperature and pressure is reduced, thereby returning the vapor to liquid.

How do heat pumps benefit the environment?

The heat pump moves already existing heat, rather than using energy to generate more heat. The modern domestic heat pump for water operates in a simple and energy efficient manner. Only a small amount of water is used to drive the compressor, and the heat energy produced can be up to four times the electrical energy used to drive the compressor. This brings your energy used for water heating down by a division of four.

The heat pump does not rely on solar energy, or direct radiation, but it can draw heat from the surrounding air – even in cold climates. As a quiet and unassuming mechanism, the heat pump does not draw attention to itself, nor does it emit any greenhouse gases.

Get yourself a heat pump

Heat pumps are best used for moderate climates. They can either be installed on the ground or on brackets on the wall. They are easy to maintain and can make your life a lot more comfortable – in an energy efficient way. The best advice for a heat pump is to speak to an informed outlet that can suggest the perfect heat pump for your needs. Even better, approach a company that also offers installation and repairs. Art Plumbing, Air Conditioning & Electric offers all these services amongst others.