Back-boiler removal and combi conversion in Somerset homes
Back boilers were fitted in tens of thousands of 60s and 70s homes across Bath and North East Somerset. They're heavy, inefficient and often running on 15mm gas — the swap to a modern combi usually cuts fuel bills by 25–35% straight away.
The bits homeowners don't expect
The boiler itself is the easy part. It's the chimney sweep and seal, the hearth clearance, the potentially undersized gas pipe from the meter, and the tank/cylinder decommission in the loft or airing cupboard that make it a full day-and-a-half job.
What's included in the conversion
- Back-boiler and gas-fire safe isolation and removal
- Chimney swept, capped and vented to prevent damp
- 22mm gas run from meter where the existing feed is undersized
- F&E tank and hot-water cylinder removed, loft made good
- Full system flush and magnetic filter fitted before commissioning
Where the new combi is likely to go
Kitchen wall, utility, or upstairs cupboard usually beats the original hearth spot because flue routes are shorter and condensate can run to an internal waste. We'll show you two or three options on the survey.
Frequently asked
- Can I keep the fireplace?
- Yes. Once the back-boiler is out and the throat plate is sealed you can reopen it as a decorative feature or fit a modern gas or electric fire.
- How long does the whole job take?
- Typically 1.5–2 days on site. The loft tank and cylinder removal is what pushes it past a straight combi swap.
- Will the radiators still work?
- They will, but old open-vented systems accumulate a lot of sludge. A power flush and a filter are non-negotiable for us — otherwise the new combi's PCB pays the price.
The realistic quote
Send a photo of the fireplace, the hot-water cylinder and the gas meter. We'll come back with a fixed price for the whole conversion — not a combi-only figure that grows on install day.
Related solutions
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Where we cover
New Worcester boiler with a 10 year guarantee*
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