A split system heat pump is an air-to-water heat pump in two parts: an outdoor unit that collects heat from the air, and an indoor unit called a hydrobox where that heat is passed into the water for your heating and hot water. The two are connected by insulated refrigerant pipes rather than water pipes, so there is no water outside to freeze.
In Berkshire, a hydrobox often goes in an utility room or garage, with the cylinder alongside. Properties on exposed sites around Berkshire can avoid outdoor water pipes altogether with a split system. In Berkshire homes where the clearest unit position is away from the plant cupboard, a split system allows a longer route indoors.
Who it suits
- Exposed or frost-prone sites where outdoor water pipes would be a risk
- Owners who would rather not use glycol or anti-freeze valves
- Homes where the outdoor unit must sit some distance from the plant space
- Houses with indoor wall space for a boiler-sized hydrobox
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.
Split system heat pumps prices in Berkshire
The ranges below are typical installed prices for homes in Berkshire, including VAT. A survey sets the exact figure, because two similar-looking houses in Berkshire can need quite different radiators and pipework.
| Home | Typical size | Installed guide price | After £7,500 grant |
|---|---|---|---|
| 1–2 bedroom flat or small terrace | 4–5 kW | £10,050–£13,250 | £2,550–£5,750 |
| 2–3 bedroom terrace or semi | 5–7 kW | £11,150–£14,300 | £3,650–£6,800 |
| 3 bedroom semi or small detached | 6–9 kW | £12,700–£16,450 | £5,200–£8,950 |
| 4 bedroom detached | 8–12 kW | £14,850–£19,100 | £7,350–£11,600 |
| 5+ bedroom or larger older house | 11–16 kW | £17,500–£23,850 | £10,000–£16,350 |
Installed, inc VAT: unit, cylinder, controls, minor pipework and commissioning.
Towns we cover in Berkshire
We cover 10 towns in Berkshire for split system heat pumps. Each links to local guide prices and the grant position for England.
| Town | Postcode district | Nearest town | Midwinter daylight |
|---|---|---|---|
| Reading | RG1 | Lower Earley | 7 h 50 min |
| Slough | SL1 | Maidenhead | 7 h 49 min |
| Bracknell | RG12 | Crowthorne | 7 h 50 min |
| Maidenhead | SL6 | Slough | 7 h 49 min |
| Wokingham | RG40 | Crowthorne | 7 h 50 min |
| Newbury | RG14 | Thatcham | 7 h 51 min |
| Lower Earley | RG6 | Reading | 7 h 50 min |
| Crowthorne | RG45 | Sandhurst | 7 h 51 min |
| Thatcham | RG19 | Newbury | 7 h 51 min |
| Sandhurst | GU47 | Crowthorne | 7 h 51 min |
Split system heat pumps questions
How big is a hydrobox?
A hydrobox is typically about the size of a wall-mounted boiler, though sizes vary by make and model. It needs wall space near the cylinder with room around it for servicing and pipe connections. Some manufacturers combine the hydrobox and cylinder in a single floor-standing unit similar in size to a tall fridge-freezer, which can suit a utility room or garage.
Is a split system eligible for the Boiler Upgrade Scheme?
Yes. A split air-to-water heat pump counts as an air source heat pump under the scheme, so in England and Wales eligible owners of existing homes can receive £7,500, or £9,000 when replacing oil or LPG within the published dates. The MCS-certified installer applies for you. Scotland's Home Energy Scotland funding is separate, and Northern Ireland has no dedicated homeowner grant at present.
Do I need an F-gas engineer for a split heat pump?
Yes. Split systems usually use a fluorinated refrigerant such as R32, so installing, servicing or repairing the refrigerant circuit must by law be done by an F-gas certified engineer. That covers joining the refrigerant pipes, testing them for leaks and charging the system. Your quote sets out who carries out each part of the installation, including the refrigerant work.
Is a split system more efficient than a monobloc?
Not inherently. Efficiency depends far more on design, meaning correct sizing, low flow temperatures and good controls, than on whether the unit is split or monobloc. A split system can avoid the heat loss and glycol of a long outdoor water run, which helps in certain layouts. The survey estimates seasonal efficiency for the specific units proposed, so you can compare like for like.