- Area
- Greater London
- Postcode district
- BR7
- Nation
- England
- Guide price
- From £10,650 inc VAT
- Survey
- Free for installation enquiries
Gas boiler to heat pump for Chislehurst homes
In Chislehurst, as anywhere in the UK, the heat pumps that perform well are the ones designed around low flow temperatures and sized from a proper heat loss calculation.
Rear gardens and side returns in Chislehurst usually offer a sensible spot for the outdoor unit, checked for airflow and neighbours. If your Chislehurst home still cooks on gas, we talk through whether to keep the supply or switch to an induction hob.
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.
- Combi owners who can find space for a hot water cylinder
- Homes in England and Wales eligible for the Boiler Upgrade Scheme
- Households ready to give up gas entirely and drop the standing charge
What's included
- Free survey with heat loss calculation and cylinder siting
- Removal of the gas boiler, flue and any loft tanks
- Capping of the gas pipe at the boiler position where you are giving up gas
- Heat pump cylinder, outdoor unit and weather compensation controls
- System flush and radiator upgrades where the design calls for them
Installers in Chislehurst take out the old boiler and flue and seal the wall opening as part of the job.
Grants and rules for heat pumps in England
Homes in Chislehurst 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.
Guide prices for replacing a gas boiler with a heat pump in Chislehurst
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.
Short winter days in Chislehurst and what they mean
Chislehurst sees roughly 7 hours 50 minutes of daylight in late December against 16 hours 37 minutes in June. Milder southern winters suit heat pumps well, though the system is still sized for a cold snap rather than an average day.
From survey to switch-on in Chislehurst
- Send your postcode and a few details, or use the guide price tool.
- A surveyor visits your Chislehurst 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 Chislehurst: questions
How long does installation take in Chislehurst?
Most installations take 2–4 days on site. Jobs with several radiator changes or new pipework take longer, and your quote for a Chislehurst home states the expected time.
Can you service a heat pump in Chislehurst that someone else installed?
Yes. We arrange servicing and repairs for most air source heat pumps in Chislehurst, whoever fitted them. Tell us the make and model when you book.
What size heat pump does a Chislehurst home need?
It depends on the heat loss, not the postcode. As a rough guide, a 3 bedroom semi often needs 6–9 kW, but the room-by-room survey sets the actual size for your Chislehurst home.
Can a heat pump replace a combi boiler?
Yes, but you need room for a hot water cylinder, because heat pumps store hot water rather than heating it on demand. Most homes find a space in a cupboard, utility room, garage or under the stairs, and compact or combined indoor units help where space is tight. The survey measures the options first, so you know where everything will go before you accept the quote.
Should I have my gas meter removed?
If gas is used for nothing else, removing the meter ends the gas standing charge, which is about £108 a year at the October to December 2026 price cap. If you still cook on gas or have a gas fire, you will need to keep the supply. Meter removal is arranged through your gas supplier, usually once the heat pump is running; the pipe at the boiler position is capped during the installation.

