- Area
- Greater London
- Postcode district
- BR6
- Nation
- England
- Guide price
- From £10,650 inc VAT
- Survey
- Free for installation enquiries
Gas boiler to heat pump in Orpington: what to expect
Most homes can run on a heat pump if the system is designed properly, and Orpington is no different. The key is matching the heat pump and radiators to the home's heat loss.
Households across Greater London moving off gas can have a survey in Orpington that compares running costs on realistic assumptions. Semi-detached and terraced houses in Orpington often have an airing cupboard that can be reused for a heat pump cylinder.
Moving from mains gas to a heat pump means finding cylinder space, deciding what happens to the gas supply and comparing running costs on realistic assumptions.
- Boilers that are old, unreliable or due for replacement
- Combi owners who can find space for a hot water cylinder
- System or regular boiler homes with an existing airing cupboard
What's included
- Heat pump cylinder, outdoor unit and weather compensation controls
- Free survey with heat loss calculation and cylinder siting
- Commissioning, MCS certificate and grant application in England and Wales where eligible
- Removal of the gas boiler, flue and any loft tanks
- System flush and radiator upgrades where the design calls for them
Many gas-heated homes in Orpington have a combi boiler in the kitchen, so the survey starts by finding the right place for a cylinder.
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 Orpington quote.
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.
Guide prices for replacing a gas boiler with a heat pump in Orpington
These are guide prices for Greater London, installed and including VAT. Your final price is fixed in a written quote after the survey and depends on the heat loss of the house, the radiators that need changing and where the unit goes.
| Home | Typical size | Installed guide price | After £7,500 grant |
|---|---|---|---|
| 1–2 bedroom flat or small terrace | 4–5 kW | £10,650–£14,000 | £3,150–£6,500 |
| 2–3 bedroom terrace or semi | 5–7 kW | £11,750–£15,100 | £4,250–£7,600 |
| 3 bedroom semi or small detached | 6–9 kW | £13,450–£17,350 | £5,950–£9,850 |
| 4 bedroom detached | 8–12 kW | £15,700–£20,150 | £8,200–£12,650 |
| 5+ bedroom or larger older house | 11–16 kW | £18,500–£25,200 | £11,000–£17,700 |
Installed, inc VAT: unit, cylinder, controls, minor pipework and commissioning.
Designing for Orpington's winters
On the shortest day Orpington gets about 7 hours 51 minutes of daylight, and the winter sun reaches only around 15° above the horizon at noon. Winters this far south are milder than in most of the UK, which helps a heat pump run at low flow temperatures for much of the season.
From survey to switch-on in Orpington
- Send your postcode and a few details, or use the guide price tool.
- A surveyor visits your Orpington home, measures every room and checks where the outdoor unit can go.
- You receive a heat loss design and a fixed written quote, with any grant shown where it applies.
- Installers fit the unit, cylinder and any radiator changes, typically over 2–4 days on site.
- The system is commissioned, set up with weather compensation and handed over with the paperwork.
Replacing a gas boiler with a heat pump in Orpington: questions
Where would the outdoor unit go on an Orpington house?
Usually at the side or rear, on a level base with space around it for airflow and servicing, away from bedroom windows where possible. The surveyor checks positions at your Orpington home.
How soon can you survey a home in Orpington?
Survey dates depend on how busy installers are in Greater London. We offer the next available dates when you enquire and confirm them in writing.
Can you service a heat pump in Orpington that someone else installed?
Yes. We arrange servicing and repairs for most air source heat pumps in Orpington, whoever fitted them. Tell us the make and model when you book.
Is there a grant to replace a gas boiler with a heat pump?
In England and Wales, the Boiler Upgrade Scheme gives £7,500 towards an air-to-water heat pump that replaces a gas boiler, for eligible owners of existing homes. The MCS-certified installer applies to Ofgem and deducts the grant from your quote, and Ofgem contacts you to confirm. Scotland has separate Home Energy Scotland funding, and Northern Ireland has no dedicated homeowner grant at present.
Do I need to replace the cylinder I already have?
Usually, yes. Older cylinders have a small internal coil designed for water from a boiler at around 60–70°C, and they cannot take in heat quickly enough at the lower temperatures a heat pump runs at. A heat pump cylinder has a larger coil. On its own, a cylinder supplied and fitted has a guide price of £1,200–£2,200, installed and including VAT, though it is normally part of the full system price.