With the arrival of some very welcome warmer weather, you might think it’s the wrong season to talk about heat pumps. But actually, they can be very efficient at cooling your home too.
Installing a heat pump offers a lower-carbon and lower-cost alternative to air-conditioning or chiller systems. It also means that you just need one system to heat and cool your home. And with the past few summers we’ve had in the UK, this would probably be very welcome.
Heat pumps can work in reverse to take the warm air out of your home. They do this through either passive cooling or active cooling and the technique depends on your system.
Passive cooling provides ultra low-cost cooling and increases efficiency by removing warm air from the building. The low temperature of the ground or air cools the property via a fan coil by passing brine (water and refrigerant mixture) through a plate heat exchanger (plates that exchange heat between fluids). Ground source heat pumps that do this are especially efficient as they can charge the ground with the heat from your home in the summer ready to be extracted in the winter. This type of cooling is often referred to as natural cooling as, apart from the circulation pump and control unit, the heat pump remains switched off.
Active cooling reverses the function of the heat pump by generating chilled water or air to cool the property. Like a fridge, these actively generate cool temperatures. If you have an air to water system the chilled water is channeled via the compressor turning the gas into a liquid to cool the interior of your building. If you have an air to air system the air would pass over the interior coils and cool down as the brine heats up.The pump then pushes the cool air into your home.
Active cooling tends to be more effective than passive systems with similar performance levels as air conditioning, and is more affordable and environmentally friendly. Although it is more expensive to run than natural passive systems.
Is the cooling function of heat pumps a good selling point for you? With recent summers it certainly makes sense to install these rather than air-con right?