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 Oxfordshire with loft tanks can usually have them removed when an unvented cylinder is fitted. In terraced homes around Oxfordshire and across Oxfordshire, slimline cylinders can fit spaces a standard model cannot. Cylinder sizes for Oxfordshire homes are based on the people living there and the bathrooms in daily use.
Who it suits
- Households with older vented cylinders and loft tanks who want mains-pressure showers
- Homes replacing a combi boiler that need space found for a cylinder
- Larger families or homes with two or more bathrooms
- Homes with solar PV that want to store daytime electricity as hot water
Grants and rules for heat pumps in England
Homes in Oxfordshire 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.
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 Oxfordshire
Here are typical prices for heat pump hot water cylinders in Oxfordshire, 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) | £1,250–£2,300 |
Supplied and fitted, inc VAT. Included in every full system price.
Towns we cover in Oxfordshire
We cover 11 towns in Oxfordshire 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 |
|---|---|---|---|
| Oxford | OX1 | Abingdon | 7 h 47 min |
| Banbury | OX16 | Brackley | 7 h 44 min |
| Abingdon | OX14 | Didcot | 7 h 48 min |
| Bicester | OX26 | Oxford | 7 h 45 min |
| Didcot | OX11 | Abingdon | 7 h 48 min |
| Witney | OX28 | Oxford | 7 h 47 min |
| Chipping Norton | OX7 | Stow-on-the-Wold | 7 h 45 min |
| Henley-on-Thames | RG9 | Marlow | 7 h 49 min |
| Thame | OX9 | Princes Risborough | 7 h 47 min |
| Wallingford | OX10 | Didcot | 7 h 49 min |
| Wantage | OX12 | Didcot | 7 h 49 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.
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.
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.

