The heat pump circulates a mixture of water and antifreeze in a buried loop of pipe, called a ground loop. The fluid absorbs heat from the ground, and is then pumped through a heat exchanger. It’s then passed through a compressor, and concentrated to a higher temperature, capable of heating water for radiators, underfloor heating and hot water circuits. The ground loop fluid, now cooler, passes back into the ground, and the process repeats.
The length of the ground loop depends on the size of your property, and how much heat you need. Longer ground loops can draw more heat from the ground, but they need more space in which to be buried. Normally, the pipe is buried in one metre deep trenches. However, if there’s not enough space in your garden for this, a vertical loop can be installed, in a borehole. When we visit your property, we’ll determine which system is right for you, and design a system to suit your particular needs.
Unlike gas or oil boilers, a heat pump delivers a lower temperature over a long period. During the winter, you may need to leave it on all the time to heat your house efficiently. It also means that your radiators won’t feel as hot to the touch as they do with a gas or oil boiler.
You’ll need to consider a few things to see if a ground source heat pump is right for you:
It doesn’t have to be particularly big, but as we need to be able to put in either a trench or borehole, we need to be able to get in with digging equipment.
Because the heat pump produces a lower temperature than a traditional boiler, it’s important that your home is draught proofed, and well insulated. It can also make the system smaller, and cheaper.
If you’re replacing an oil, LPG, electric or coal system, a heat pump will save you money on your heating bills. We don’t recommend heat pumps for homes on the gas network.
Underfloor heating, low temperature fan convectors or larger radiators can work better than standard radiators, because of the lower water temperatures required.
If you’re combining the installation with other building work, the cost can be lowered.
Installing a typical system will start from around £10,000. There are various grants and loans to help with these costs. Running costs will vary, depending on the size of your home, and how well insulated it is. The savings you’re able to make will vary, depending on a number of factors:
If you’re in a position to do so, underfloor heating often provides greater efficiencies than radiators. If it’s not possible, then use the largest radiators you can.
The pump is powered by electricity, so you will still have some fuel costs. The savings will depend on the price of the fuel you’re replacing, and that of the electricity to power the pump.
If your old system was inefficient, then the saving you’ll achieve with the pump system will be higher than if it ran efficiently.
Your thermostat should be set between 18-21C. If you dramatically increase the temperature of your house post-installation, your heating bills will very likely increase.
We advise that you take some time and learn how to control the system, so you can get the most out of it. We will explain this before we leave, as well as providing a handover pack including manuals. We can also give you advice about how to control the system to make it most effective.