The trade-off is that the pipes between the outdoor unit and the house carry water, so they must be protected from freezing. That is done with glycol (an anti-freeze) in the system or with anti-freeze valves that release water from the outdoor pipework if it nears freezing, for example during a power cut in cold weather. Keeping the outdoor pipe run short and well insulated also helps efficiency.
Semi-detached homes in Berkshire often have a side wall where a monobloc unit can sit on a frame, clear of the path. In exposed spots around Berkshire, frost protection for the outdoor pipework is chosen with the site in mind. Bungalows in Berkshire often let the unit sit right beside the plant cupboard, keeping water pipes short.
Who it suits
- Houses and bungalows with outdoor space close to where pipes enter the home
- Households that want to keep refrigerant work out of routine servicing
- Homes where the unit can sit within a short pipe run of the cylinder
- Owners who want the simplest installation, with no indoor refrigerant
Grants and rules for heat pumps in England
Homes in Berkshire 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.
Monobloc 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 monobloc 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 |
Monobloc heat pumps questions
What is the difference between monobloc and split heat pumps?
A monobloc unit holds all of its refrigerant in the outdoor unit and sends heated water into the house. A split system has an outdoor unit and an indoor unit called a hydrobox, connected by refrigerant pipes, with heat passed to water indoors. Monobloc installs are simpler; splits avoid outdoor water pipes but need an F-gas certified engineer for the refrigerant work. Our monobloc vs split guide compares them.
Is glycol or anti-freeze valves the better option?
Neither is right for every home. Glycol gives reliable frost protection without draining but slightly reduces efficiency and needs its concentration checked at servicing. Anti-freeze valves keep the system water plain but release water if pipes near freezing during a power cut, so the system then needs refilling. The installer recommends one based on the unit, pipe run and how exposed the site is.
What refrigerant do monobloc heat pumps use?
Most use R32 or R290. R290 is propane, a natural refrigerant with a very low global warming impact, and some models use it to reach higher flow temperatures. Because R290 is flammable, manufacturers set clearance zones around the unit from openings such as windows, doors and drains, which the survey takes into account when choosing a position.
How far can a monobloc unit be from the house?
Usually as close as practical, because water pipes outside lose heat and need frost protection. Manufacturers set limits on pipe length and size, and longer runs need larger, better-insulated pipes. Most homes site the unit against or near an outside wall close to where the pipes enter. If the only good position is far from the house, a split system may suit better.