Most heat pump cylinders are unvented, meaning they run at mains water pressure and give strong flow from every tap without a cold water tank in the loft. Unvented cylinders have safety controls that must be fitted and checked by someone qualified to work on them. We size the cylinder from your household and bathrooms, confirm your mains water supply can support it, and plan the space, pipework and discharge route at the survey.
Older houses in Cornwall with loft tanks can usually have them removed when an unvented cylinder is fitted. Cylinder sizes for Cornwall homes are based on the people living there and the bathrooms in daily use. In terraced homes around Cornwall and across Cornwall, slimline cylinders can fit spaces a standard model cannot.
Who it suits
- Households with older vented cylinders and loft tanks who want mains-pressure showers
- Every air-to-water heat pump installation, whatever the existing boiler
- 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
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 Cornwall
The ranges below are typical installed prices for homes in Cornwall, including VAT. A survey sets the exact figure, because two similar-looking houses in Cornwall can need quite different radiators and pipework.
| Work | Guide price |
|---|---|
| Heat pump hot water cylinder (supplied and fitted) | £1,250–£2,250 |
Supplied and fitted, inc VAT. Included in every full system price.
Towns we cover in Cornwall
We cover 15 towns in Cornwall 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 |
|---|---|---|---|
| Redruth | TR16 | Camborne | 8 h 02 min |
| Falmouth | TR11 | Truro | 8 h 03 min |
| St Austell | PL25 | Bodmin | 8 h 01 min |
| Truro | TR1 | Falmouth | 8 h 02 min |
| Camborne | TR14 | Redruth | 8 h 02 min |
| Newquay | TR7 | Truro | 8 h 00 min |
| Penzance | TR18 | Hayle | 8 h 03 min |
| Bodmin | PL31 | Wadebridge | 8 h 00 min |
| Saltash | PL12 | Plymouth | 8 h 00 min |
| Bude | EX23 | Launceston | 7 h 56 min |
| Hayle | TR27 | Camborne | 8 h 02 min |
| Helston | TR13 | Camborne | 8 h 03 min |
| Launceston | PL15 | Liskeard | 7 h 58 min |
| Liskeard | PL14 | Saltash | 8 h 00 min |
| Wadebridge | PL27 | Bodmin | 7 h 59 min |
Heat pump hot water cylinders questions
How much does a heat pump cylinder cost?
A heat pump hot water cylinder has a guide price of £1,200–£2,200, installed and including VAT. In a full heat pump installation the cylinder is already included in the system guide price, so this figure mainly applies where a cylinder is replaced on its own. Capacity, coil design and the pipework needed affect where your price sits.
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.
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.