Greater Manchester
In short
In Bolton the fault code on the display usually lies — the real problem is a scaled plate exchanger three feet away from the boiler cover.
Bolton is a heavy Worcester Bosch town — most combis are 8–14 years old, fitted during the 2010–2016 Green Deal push. Older Halliwell and Astley Bridge terraces still have 20-year Potterton Suprima system boilers with hot-water cylinders in the airing cupboard.
Two Bolton patterns dominate: 10-year Worcester Greenstar combis in Halliwell and Farnworth losing hot-water performance because the plate heat exchanger is furred with limescale, and older Potterton or Ideal Mexico system boilers on Astley Bridge and Bromley Cross where the pump is seized after a winter off. We descale rather than replace where we can — it's usually £200 vs £600.
Local hardness: Moderately hard (typically 100–160 mg/L CaCO₃) — noticeably harder than central Manchester
Bolton sits on the harder end of United Utilities' northwest supply (roughly 150–200 mg/L CaCO₃ in parts of BL4/BL5). Scale on plate heat exchangers is a real Bolton fault — we descale on-site with a Kamco flush kit rather than swapping the exchanger.
£130–£340 for typical combi faults; plate-exchanger descale £160–£240; system-boiler repairs £180–£420.
Every price is confirmed in writing after the £50 diagnostic. Nothing billable starts until you approve the fair fixed quote — and if we can't fix the fault we diagnosed, the £50 is refunded.
If a Bolton engineer diagnoses "failed heat exchanger" on a Worcester Greenstar without running a hot-water flow test and without checking the plate exchanger with a strip-down, they're either guessing or upselling. Real diagnosis takes 20 minutes and a torque driver, not a sales pitch.
Our promise on every Bolton boiler-repair call-out: £50 to attend and diagnose, a fair fixed quote in writing before any billable repair starts, and the £50 refunded if we can't fix the fault.
"Combi was making a kettling noise loud enough to hear downstairs. Diagnosed heat exchanger scaling from the hard water, flushed the system, fitted a filter, quieter than new."
— Mike P., Astley Bridge · Combi descale and magnetic filter, Astley Bridge
"Outside tap burst in the January freeze. Turned up the same afternoon, replaced the tap, fitted an internal isolator and lagged the pipework. Fair fixed price."
— Jane C., Horwich · Burst outside tap, Horwich
"Back boiler had been leaking into the fireplace for months. KJ removed it, capped the gas, fitted a new combi upstairs, and made good the wall. Explained everything clearly."
— Rashid A., Great Lever · Back-boiler removal and combi install, Great Lever
Fixed £50 diagnostic
Flat fee. No hourly meter running.
Fair quote or refund
Transparent pricing — refunded if we don't fix it.
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Boiler playing up in Bolton?
Call 01706 318200 or start a chat — we'll book a £50 diagnostic at a time that suits you.
KJ
Founder, KJ Plumbers · Online now
KJ
onlineHonest UK plumbing advice — free where safe, £50 home visit only if needed.
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