Every air-to-water heat pump installation needs a cylinder, because there is no heat pump equivalent of a combi boiler that heats water instantly. If you have a combi now, the main design question is where the cylinder will go. If you already have a cylinder, it will almost always need replacing with a heat pump model, though the same cupboard can often be reused if it is large enough.
Discharge pipe routes are planned at the survey so a Wiltshire cylinder can drain safely to the outside. Many homes in Wiltshire with combi boilers have no airing cupboard, so the survey looks for the most practical cylinder space. Cylinder sizes for Wiltshire homes are based on the people living there and the bathrooms in daily use.
Who it suits
- Homes with solar PV that want to store daytime electricity as hot water
- Larger families or homes with two or more bathrooms
- Every air-to-water heat pump installation, whatever the existing boiler
- Homes replacing a combi boiler that need space found for a cylinder
Grants and rules for heat pumps in England
In England the Boiler Upgrade Scheme gives £7,500 towards an air source heat pump (£9,000 if it replaces oil or LPG, from 21 July 2026 to 31 March 2027), and since 28 April 2026 a valid EPC is no longer needed. The grant is applied for by the MCS-certified installer and shown as a deduction on your quote.
There is no VAT on installing a heat pump anywhere in the UK until 31 March 2027. In England most houses can have an air source heat pump under permitted development, provided the unit meets the MCS noise and siting standards; the old 1 m boundary limit was removed on 29 May 2025. We flag listed buildings, flats and sensitive conservation-area positions at survey.
Heat pump hot water cylinders prices in Wiltshire
These are guide prices for Wiltshire, installed and including VAT. Your final price is fixed in a written quote after the survey and depends on the heat loss of the house, the radiators that need changing and where the unit goes.
| Work | Guide price |
|---|---|
| Heat pump hot water cylinder (supplied and fitted) | £1,200–£2,200 |
Supplied and fitted, inc VAT. Included in every full system price.
Towns we cover in Wiltshire
We cover 12 towns in Wiltshire for heat pump hot water cylinders. Each links to local guide prices and the grant position for England.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Swindon | SN1 | Marlborough | 7 h 49 min |
| Salisbury | SP1 | Amesbury | 7 h 54 min |
| Trowbridge | BA14 | Bradford-on-Avon | 7 h 51 min |
| Chippenham | SN15 | Corsham | 7 h 50 min |
| Melksham | SN12 | Corsham | 7 h 51 min |
| Warminster | BA12 | Trowbridge | 7 h 53 min |
| Calne | SN11 | Chippenham | 7 h 50 min |
| Devizes | SN10 | Calne | 7 h 51 min |
| Amesbury | SP4 | Salisbury | 7 h 53 min |
| Bradford-on-Avon | BA15 | Trowbridge | 7 h 51 min |
| Corsham | SN13 | Chippenham | 7 h 50 min |
| Marlborough | SN8 | Swindon | 7 h 50 min |
Heat pump hot water cylinders questions
I have a combi boiler. Where will the cylinder go?
Moving from a combi to a heat pump means finding space for a cylinder, usually somewhere around 600 mm square and up to about 2 m tall. Common choices are a bedroom or landing cupboard, a utility room, under the stairs or an integral garage. The surveyor looks at your layout and suggests options, including slimline models where space is tight.
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.
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.