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.
Many homes in Devon with combi boilers have no airing cupboard, so the survey looks for the most practical cylinder space. Older houses in Devon with loft tanks can usually have them removed when an unvented cylinder is fitted. Discharge pipe routes are planned at the survey so a Devon cylinder can drain safely to the outside.
Who it suits
- Households with older vented cylinders and loft tanks who want mains-pressure showers
- Homes with solar PV that want to store daytime electricity as hot water
- Homes replacing a combi boiler that need space found for a cylinder
- Every air-to-water heat pump installation, whatever the existing boiler
Grants and rules for heat pumps in England
Homes in Devon can use the Boiler Upgrade Scheme, which takes £7,500 off the cost of an air source heat pump when it replaces fossil-fuel or electric heating. Replacing oil or LPG heating qualifies for £9,000 for installations from 21 July 2026 to 31 March 2027, and air-to-air systems for £2,500. The MCS-certified installer named in your quote applies for the grant and deducts it from the price.
Installing heat pumps is zero-rated for VAT across the UK until 31 March 2027. Since 29 May 2025, permitted development in England allows up to two air source heat pumps on a house, each up to 1.5 m³, with no blanket 1 m boundary rule — the installation must still meet the MCS planning standards, including the noise check. Listed buildings, flats and some conservation-area positions need extra consent, which we check at survey.
Heat pump hot water cylinders prices in Devon
Here are typical prices for heat pump hot water cylinders in Devon, 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) | £1,200–£2,200 |
Supplied and fitted, inc VAT. Included in every full system price.
Towns we cover in Devon
We cover 18 towns in Devon 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 |
|---|---|---|---|
| Plymouth | PL1 | Saltash | 8 h 01 min |
| Exeter | EX4 | Crediton | 7 h 57 min |
| Paignton | TQ3 | Torquay | 8 h 00 min |
| Torquay | TQ1 | Paignton | 8 h 00 min |
| Newton Abbot | TQ12 | Torquay | 7 h 59 min |
| Exmouth | EX8 | Sidmouth | 7 h 58 min |
| Barnstaple | EX31 | Bideford | 7 h 54 min |
| Bideford | EX39 | Barnstaple | 7 h 54 min |
| Tiverton | EX16 | Crediton | 7 h 56 min |
| Crediton | EX17 | Exeter | 7 h 57 min |
| Dartmouth | TQ6 | Paignton | 8 h 01 min |
| Honiton | EX14 | Sidmouth | 7 h 57 min |
| Ilfracombe | EX34 | Barnstaple | 7 h 52 min |
| Kingsbridge | TQ7 | Dartmouth | 8 h 02 min |
| Okehampton | EX20 | Tavistock | 7 h 57 min |
| Sidmouth | EX10 | Honiton | 7 h 58 min |
| Tavistock | PL19 | Plymouth | 7 h 59 min |
| Totnes | TQ9 | Paignton | 8 h 00 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.
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.
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.
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.

