- Area
- Greater London
- Postcode district
- SM5
- Nation
- England
- Guide price
- From £10,650 inc VAT
- Survey
- Free for installation enquiries
What to know about replacing a gas boiler with a heat pump in Carshalton
Every property in Carshalton is different, so the design starts from measurements rather than a rule of thumb. That keeps the system the right size and the running costs predictable.
Households across Greater London moving off gas can have a survey in Carshalton that compares running costs on realistic assumptions. If your Carshalton 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.
- Homes in England and Wales eligible for the Boiler Upgrade Scheme
- System or regular boiler homes with an existing airing cupboard
- 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
- Commissioning, MCS certificate and grant application in England and Wales where eligible
- Capping of the gas pipe at the boiler position where you are giving up gas
- Free survey with heat loss calculation and cylinder siting
Installers in Carshalton 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 Carshalton 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.
Gas boiler to heat pump prices in Carshalton
Guide prices for Carshalton 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 Carshalton and what they mean
Carshalton sees roughly 7 hours 51 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 Carshalton
- Start online with a guide price or call us.
- A home survey in Carshalton gives us the room-by-room heat loss.
- Your written quote sets out the design, the price and the grant position where you live.
- Installation is booked for dates that suit you; most homes take 2–4 days on site.
- After commissioning you get a handover of the controls and settings, plus the certificates.
Replacing a gas boiler with a heat pump in Carshalton: questions
How soon can you survey a home in Carshalton?
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.
How long does a heat pump survey take in Carshalton?
A home survey in Carshalton usually takes one to two hours. The surveyor measures every heated room, checks windows, walls and radiators, and looks at where the outdoor unit and cylinder can go.
Where would the outdoor unit go on a Carshalton 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 Carshalton home.
Will my hot water run out with a heat pump?
Not if the cylinder is sized properly for your household. The survey asks how many people live in the home, how many bathrooms you have and whether you prefer baths or showers, then sizes the cylinder to suit. The heat pump reheats the cylinder on a schedule, often overnight and again during the day, and an immersion heater acts as a backup.
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.