- Area
- Greater London
- Postcode district
- SE26
- Nation
- England
- Guide price
- From £10,650 inc VAT
- Survey
- Free for installation enquiries
Gas boiler to heat pump for Sydenham homes
Most homes can run on a heat pump if the system is designed properly, and Sydenham is no different. The key is matching the heat pump and radiators to the home's heat loss.
Semi-detached and terraced houses in Sydenham often have an airing cupboard that can be reused for a heat pump cylinder. If your Sydenham 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.
- System or regular boiler homes with an existing airing cupboard
- Combi owners who can find space for a hot water cylinder
- Households ready to give up gas entirely and drop the standing charge
What's included
- Heat pump cylinder, outdoor unit and weather compensation controls
- 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
- Commissioning, MCS certificate and grant application in England and Wales where eligible
- Free survey with heat loss calculation and cylinder siting
Many gas-heated homes in Sydenham 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 Sydenham 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.
What to budget for replacing a gas boiler with a heat pump in Sydenham
Guide prices for Sydenham and the rest of Greater London are shown below, installed and inc VAT. We publish ranges rather than a single figure because design details move the price, and the written quote after survey fixes it.
| 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 Sydenham and what they mean
Sydenham 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.
The steps for replacing a gas boiler with a heat pump in Sydenham
- Tell us about your home: postcode, property type and current heating.
- We book a survey in Sydenham; the surveyor measures rooms, windows and radiators and looks at cylinder space.
- The design and quote arrive in writing, including radiator changes and the outdoor unit position.
- On installation days the old system is removed and the new one fitted and filled.
- We commission the heat pump, show you the controls and register the installation.
Replacing a gas boiler with a heat pump in Sydenham: questions
Do you cover Forest Hill as well as Sydenham?
Yes. We arrange surveys and installation in Forest Hill, which is about a mile north of Sydenham, and across Greater London.
How long does installation take in Sydenham?
Most installations take 2–4 days on site. Jobs with several radiator changes or new pipework take longer, and your quote for a Sydenham home states the expected time.
What size heat pump does a Sydenham 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 Sydenham home.
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.
What if my gas boiler is fairly new?
A newer boiler can still be replaced, but the timing is worth weighing. Some owners switch when the boiler needs a major repair; others prefer to plan the change for a convenient time. Across the UK, heat pump installation is zero-rated for VAT until 31 March 2027. A hybrid system, which keeps the boiler alongside a heat pump, is another option, though it is not eligible for the Boiler Upgrade Scheme in England and Wales.