{"id":1122,"date":"2024-01-05T16:25:22","date_gmt":"2024-01-05T16:25:22","guid":{"rendered":"https:\/\/www.zerochippenham.org\/?p=1122"},"modified":"2024-01-05T16:25:22","modified_gmt":"2024-01-05T16:25:22","slug":"living-with-an-air-source-heat-pump","status":"publish","type":"post","link":"https:\/\/www.zerochippenham.org\/2024\/01\/05\/living-with-an-air-source-heat-pump\/","title":{"rendered":"Living with an Air Source Heat Pump"},"content":{"rendered":"

Zero Chippenham member James Bradbury talks about his experience of installing and living with an Air Soured heat pump. James’ house is a 1980s standard Chippenham estate house with two minor extensions. It has cavity wall insulation.<\/p>\n

Introduction<\/h1>\n

I’ve been seeing a lot of interest online about heat pumps and some confusion about what they are and how they work. We had one installed in our home a couple of months ago. We’re pleased with it and I’ll describe our experiences below, but first I’ll give a quick intro to heat pumps.<\/p>\n

What is a heat pump?<\/h1>\n

A heat pump is an electrically powered device for moving heat from one place to another. This is in contrast to direct heating which turns electricity into heat. In the domestic setting this means getting heat from some outside source and moving it into the building for heating or hot water. Crucially the pump’s output temperatures can be significantly higher than the input.<\/p>\n

If that seems like magic, think about what a refrigerator does. A heat pump does the same in reverse – moving heat from one place to another.<\/p>\n

Because of this, heat pumps are much more efficient than direct heating. In good conditions a modern air source heat pump can provide 3 to 4kW of heat for each kW of electricity consumed.<\/p>\n

What kinds of heat pumps are there?<\/h1>\n

Heat pumps come in at least three flavours, depending on the source of heat they use.<\/p>\n

Air-source heat pumps (ASHP) are most popular as they can be installed in most places. They typically have a large fan to pass ambient air over the heat sink. They will work at air temperatures as low as -20 degrees C and are popular in Scandanavia, but become less efficient as the outside temperature drops.<\/p>\n

Gound-source heat pumps take heat from underground, sometimes a pair of deep boreholes, or shallow pipes over a large area. The ground stores a large amount of heat accumulated over many months. GSHPs have the advantage that they are not affected by air temperature so can achieve better average efficiencies. The downside is that they need more space to install and the work is messy and expensive.<\/p>\n

Water-source heat pumps take heat from a natural water source such as a river. I don’t know much about them as they are less common. I would imagine they are cheaper than ground source heat pumps and more efficient than air-source due to the flow of water. I suppose the risk might be that the water source either freezes or dries up.<\/p>\n

In the UK most heat pumps provide heat to common water-filled radiators and hot water system, making them compatible with most legacy central heating systems. I understand that in countries with hotter climates they often provide warm and cold air to heat and cool the room with the same equipment.<\/p>\n

For more in-depth information on heat pumps, see this guide from the Energy Saving Trust.<\/p>\n

Our experience of an air-source heat pump<\/h1>\n

Our heat pump was installed in early February 2023. We made use of the UK’s Boiler Upgrade Scheme to get \u00a35000 towards the cost of our heat pump. In addition we paid around another \u00a310000 including all parts and labor. We had a Mitsubishi Ecodan on the recommendation of a local company who had themselves been recommended by a friend. In retrospect, while their equipment is said to be reliable, Mitsubishi have rather dubious ethical credentials and if choosing again we might go for a Vaillant, Kensa or MasterTherm.<\/p>\n

Installation<\/h1>\n

Our install was slightly complicated as we have some 8mm mircobore piping in our house. This means we needed an extra buffer tank so that the central heating water can be pumped around faster than the heat pump water. That added an extra \u00a3800 to the bill and took a little more space in our garage.<\/p>\n

Copper pipes and water cyclinders attached to the wall inside a garage.<\/p>\n

Speaking of space, we used a fair bit of space in the garage for the hot water cylinder, aforementioned buffer tank and a lot of pipework. This had to be linked to the condenser outside, which meant two wide copper pipes and a few wires through a few walls and across our kitchen wall. We discussed where this should go with the installers and they came up with a good solution keeping the distance as short as possible. This keeps costs and heat loss down. All the pipes were insulated by the installers, although I added a bit extra to the fiddly bits myself.<\/p>\n

In addition to the heat pump and piping, we took the installers’ advice and upgraded three radiators. Two of these needed upgrading anyway as they were rather rusty.<\/p>\n\t

\n\t\t\t\t\t\t\t\t
\n\t\t\t\"heat\t\t\t\t\t\t\n\t\t\t\t\t<\/div>\n\t\t\t\t\t\t\t\t\n