A heat pump hot water cylinder is an insulated tank that stores hot water heated by the heat pump, with a much larger internal coil than a cylinder designed for a boiler. Heat pumps heat water to a lower temperature than boilers, typically around 45–55°C, so a bigger coil is needed to pass heat into the stored water quickly. A standard boiler cylinder would heat slowly and make the heat pump work harder than it should.
Older houses in the Highlands and Islands with loft tanks can usually have them removed when an unvented cylinder is fitted. We check mains water pressure and flow at each the Highlands and Islands property before choosing a cylinder. Many homes in the Highlands and Islands with combi boilers have no airing cupboard, so the survey looks for the most practical cylinder space.
Who it suits
- Homes replacing a combi boiler that need space found for a cylinder
- Homes with solar PV that want to store daytime electricity as hot water
- Larger families or homes with two or more bathrooms
- Households with older vented cylinders and loft tanks who want mains-pressure showers
Grants and rules for heat pumps in Scotland
The Boiler Upgrade Scheme does not apply in Scotland. Instead, homeowners in the Highlands and Islands can apply to Home Energy Scotland for a grant of up to £7,500 towards a heat pump, with up to £1,500 more for eligible rural and island homes, plus an optional interest-free loan of up to £7,500. You need a written funding offer before any work starts.
There is no VAT on installing a heat pump anywhere in the UK, Scotland included, until 31 March 2027. Scottish permitted development rules and building standards apply, and the surveyor checks the unit position and any listed or conservation-area constraints.
Heat pump hot water cylinders prices in the Highlands and Islands
Here are typical prices for heat pump hot water cylinders in the Highlands and Islands, installed and including VAT. Use the guide price tool for a figure based on your home, then a survey confirms it in writing.
| Work | Guide price |
|---|---|
| Heat pump hot water cylinder (supplied and fitted) | £1,350–£2,450 |
Supplied and fitted, inc VAT. Included in every full system price.
Towns we cover in the Highlands and Islands
We cover 12 towns in the Highlands and Islands for heat pump hot water cylinders. Each links to local guide prices and the grant position for Scotland.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Inverness | IV1 | Dingwall | 6 h 35 min |
| Fort William | PH33 | Oban | 6 h 45 min |
| Aviemore | PH22 | Inverness | 6 h 40 min |
| Dingwall | IV15 | Inverness | 6 h 34 min |
| Kirkwall | KW15 | – | 6 h 11 min |
| Lerwick | ZE1 | – | 5 h 49 min |
| Nairn | IV12 | Forres | 6 h 34 min |
| Portree | IV51 | – | 6 h 36 min |
| Stornoway | HS1 | – | 6 h 24 min |
| Thurso | KW14 | Wick | 6 h 17 min |
| Ullapool | IV26 | Dingwall | 6 h 29 min |
| Wick | KW1 | Thurso | 6 h 20 min |
Heat pump hot water cylinders questions
Will I run out of hot water with a heat pump?
Not if the cylinder is sized to how your household uses hot water. Unlike a combi, hot water is stored, so very heavy use, such as several long showers back to back, can use up the stored volume before it reheats. Sizing for your busiest period, and timing reheats sensibly, avoids this for most homes.
Can I keep my existing hot water cylinder with a heat pump?
Usually not. Cylinders designed for boilers have a small coil that cannot transfer heat quickly at heat pump temperatures, so the water would reheat slowly and efficiency would suffer. A heat pump cylinder has a much larger coil. The new cylinder can often go in the same cupboard, though, if there is enough height and floor space.
Do I need good water pressure for an unvented cylinder?
Yes. An unvented cylinder runs at mains pressure, so it needs enough incoming pressure and flow to supply your taps and showers well. We measure your mains supply at the survey. If flow is low, options include a different cylinder type or an upgrade to the incoming supply pipe, which we explain before you commit.
Does a heat pump cylinder need servicing?
Yes. An unvented cylinder's safety devices should be checked every year, including the relief valves, the expansion vessel charge and the discharge pipework. This is normally done as part of the annual heat pump service, and it is often a condition of the cylinder manufacturer's warranty. Keep the cylinder paperwork with your heat pump handover documents.