Air source heat pump
Your home may be fitted with an Air Source Heat Pump (sometimes called an air-to-water heat pump) to heat your home.
It works by transferring heat from the outside air to the water in your central heating system. The Air Source Heat Pump (ASHP) captures outside air which is blown over a network of tubes filled with a refrigerant. This warms up, and it turns from a liquid into a gas. It’s passed through a compressor, into a heat exchanger and surrounded by cool water, making it warm. This warm water is then circulated around your home through underfloor heating and radiators to provide heating and hot water.
The heat pump is designed to work in heating with a low to medium flow temperature. The temperature of the water flowing through your heating system will be between 35-45°C, rather than 60-80°C, which would be the case for a traditional gas boiler system.
Radiators will feel cooler to touch compared to a traditional system, but they will be sized to ensure each room stays warm and comfortable, even on the coldest days. An ASHP will operate continuously to maintain the room temperatures set on the thermostat, rather than a gas boiler system which tends to react more quickly – providing intense heating to reach required temperatures, which may take shorter periods.
To get the best from your new heat pump heating system, the controls and settings are very important and we’d recommend the manufacturer’s settings are left unaltered; amending these could impact on the system’s efficiency and lifespan. Please refer to the manufacturer’s guidance for more information.
Conventional boiler system
If you have a boiler and an airing cupboard containing a hot water cylinder that looks a bit like the one to the left, then you have a conventional boiler.
This type of boiler heats water and stores it in the cylinder in your airing cupboard, ready for when you need it. This means that it is possible to run out of hot water (for instance if the shower is being used a lot). It also means that you have an immersion heater.
This is an electric heater built into the cylinder that can give you a boost of hot water if you run out, or if your boiler is not working. This should only be used as a back-up system and run for short periods.
Combi boiler system
If you have a boiler but no airing cupboard, you have what is known as a combi boiler. This type of system produces hot water on demand, directly heating mains cold water and piping it to your bath or shower when you need it. With this system if your boiler stops working you’ll lose both heating and hot water.
