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Glow-worm Boiler Support
Glow-worm specialists across Wokingham · Arborfield · Earley · Woodley · Finchampstead · Shinfield · Winnersh · RG40 · RG41
Glow-worm specialists · Gas Safe 599015 · F75 experts · RG40
Glow-worm support · Wokingham & RG40
Glow-worm Boiler Support — Wokingham, Berkshire
Flexicom, Ultracom, Energy & Betacom — fault codes, manuals & local repairs across Wokingham and RG40
Whether your Glow-worm boiler is showing an F22, F1 or the notorious F75 fault code, needs its annual service, or has broken down entirely — Thermotec is Wokingham’s local Gas Safe specialist. Fixed prices, exact arrival times, same-day where available. Calls answered 24/7.
£96
Service &
diagnostic
diagnostic
90%
First-time
fix rate
fix rate
Same day
Where
available
available
130+
5★ Google
reviews
reviews
Need Glow-worm help today?
Repairs · Servicing · Fault codes · RG40
Calls answered 24/7 · Stuart follows up first thing
Annual serviceFrom £96
Diagnostic fee£96 fixed
First-time fix90%
Google reviews130+ ★
★★★★★
130+ five-star Google reviews from homeowners across Wokingham, Earley, Shinfield and RG40
Gas Safe 599015
£96 fixed diagnostic
90% first-time fix
F75 specialists
Calls answered 24/7
What do you need?
Fault codes or annual servicing?
Fault code guide
Glow-worm Fault Codes
F1, F22, F75 and more — full fault code index with severity ratings, DIY fixes and step-by-step reset guidance. Includes a dedicated F75 specialist guide.
F1, F22, F75 — full code index →
F75 pump / pressure sensor guide →
When to call an engineer →
Diagnostic from £96
Annual servicing
Glow-worm Boiler Service
Annual service by a Gas Safe registered engineer — digital Benchmark record issued same day, warranty-compliant. From £96 fixed price.
What’s included in the service →
Book your exact time online →
Landlord CP12 combo £150 →
From £96 · Fixed price
Quick fault lookup
Most common Glow-worm fault codes
These are the codes Wokingham homeowners report most often. See the full fault code guide for the complete index.
F1
Ignition fault
Boiler failed to ignite. Check gas supply. Check condensate pipe for ice in winter. Press Reset. If it returns, engineer needed.
F22
Low water pressure
Pressure below minimum. Repressurise to 1.5 bar using the filling loop. If pressure keeps dropping, hidden leak — engineer required.
F75
Pump / pressure sensor fault
Most common Glow-worm fault. Pump not detected on startup, or faulty pressure sensor. Often caused by sludge. See dedicated F75 guide.
F28
Ignition lockout
Ignition attempted and failed repeatedly. Gas supply, faulty electrode or frozen condensate. Do not keep resetting — engineer needed.
F29
Flame loss lockout
Flame detected then lost during operation. Gas valve, sensor or combustion issue. Engineer diagnosis required.
F32
Fan fault
Fan not running correctly — prevents safe flue venting. Do not reset repeatedly. Gas Safe engineer required immediately.
F75 — Glow-worm’s most common fault in Wokingham
The F75 is the fault code we see most on Glow-worm boilers across RG40. It appears when the pump isn’t detected on startup, or when the pressure sensor can’t confirm the pump is running. In Wokingham’s hard water area, the cause is often magnetic sludge restricting pump movement. We have a dedicated specialist guide covering every cause, every fix and when to replace vs repair.
Read the full F75 specialist guide →
Models we support
Glow-worm range — all models covered
Thermotec services, repairs and diagnoses all current and older Glow-worm models across Wokingham and RG40. Manuals available for download for every model.
Energy Combi
Current range
Current-generation combi. ErP compliant, efficient and compact. F75 and F22 are the most common codes on this model.
Fault code guide →
Download manual (PDF) →
Ultimate3 Combi
Current range
Premium current-generation combi with advanced controls. F75 pump fault common where system sludge is present.
Fault code guide →
Download manual (PDF) →
Energy System
System boiler
System boiler for properties with hot water cylinders. F22 low pressure and F75 pump faults are most frequently reported.
Fault code guide →
Download manual (PDF) →
Betacom4
Combi
Reliable mid-range combi. F1 ignition and F75 pump faults are common as these units age in hard water areas.
F75 specialist guide →
Download manual (PDF) →
Easicom3
Combi
Popular budget combi. Straightforward to service. F22 pressure loss and F1 ignition faults are the most reported issues.
Fault code guide →
Download manual (PDF) →
Compact Combi
Older model
Older compact combi. Still common in Wokingham homes. Parts availability checked before service or repair is quoted.
Fault code guide →
Download manual (PDF) →
Ultracom2
Older model
Older Ultracom range combi. Diverter valve and pump issues common on these models. F75 very frequently reported.
F75 specialist guide →
Download manual (PDF) →
Flexicom CX
Older model
Older Flexicom range. Still serviced across Wokingham. F75 is the most common fault on this range in hard water areas.
F75 specialist guide →
Download manual (PDF) →
PDF manuals
Download Glow-worm manuals
User, installation and servicing manuals for all major Glow-worm models. Click to download direct.
Common questions
Glow-worm boiler FAQ
What does the F75 fault code mean on a Glow-worm boiler?
F75 means the boiler’s pump wasn’t detected on startup, or the pressure sensor couldn’t confirm the pump is running. It’s the most common fault on Glow-worm boilers in Wokingham, often caused by magnetic sludge restricting pump movement in hard water areas. Full F75 specialist guide →
What does the F22 fault code mean on a Glow-worm boiler?
F22 indicates low water pressure. Repressurise to 1.5 bar using the filling loop. If pressure keeps dropping more than twice a year, there is likely a hidden leak and a Gas Safe engineer is needed.
What does the F1 fault code mean on a Glow-worm boiler?
F1 means the boiler failed to ignite. Check the gas supply and check the condensate pipe for ice in winter, then press Reset. If F1 returns immediately, an engineer is needed.
How much does a Glow-worm boiler service cost in Wokingham?
Thermotec charges from £96 fixed price for a Glow-worm annual service in Wokingham, including a full safety check, combustion analysis and digital Benchmark record. Landlord CP12 combined with a service is £150.
Why does my Glow-worm boiler keep getting the F75 fault?
Recurring F75 faults are usually caused by magnetite sludge restricting the pump, especially in Wokingham’s hard water area. A powerflush and magnetic filter typically resolve recurring F75 faults long-term, rather than repeated pump replacement alone.
Do you have Glow-worm manuals for download?
Yes — Thermotec provides downloadable PDF manuals for all major Glow-worm models including Energy Combi, Ultimate3, Energy System, Betacom4, Easicom3, Compact Combi, Ultracom2 and Flexicom CX. See the manuals section above.
Coverage
Glow-worm support across Wokingham & Berkshire
Based in Arborfield — 10 minutes from Wokingham town centre. Covering RG40, RG41, RG2, RG5, RG6 and RG45.
All services
All Thermotec services — Wokingham & RG40
Gas Safe registered across the full RG40 and RG41 area. Fixed prices, exact arrival times.
Boiler Repairs
From £96 diagnostic
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New Boiler Installation
From £1,800 · 15yr warranty
Get a quote →
Annual Boiler Service
From £96 · Digital record
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Powerflush
Clears sludge causing F75
Find out more →
Landlord CP12
From £75 · Same day cert
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Smart Thermostats
Hive, Nest, tado° from £300
Find out more →
Radiator Services
From £150 · TRVs from £60
Find out more →
Magnetic Filters
Prevent future F75 faults
Find out more →
Unvented Cylinders
G3 qualified · From £96 service
Find out more →
Water Softeners
Reduces sludge in RG40
Find out more →
Heat Pumps
£7,500 BUS grant available
Find out more →
Plumbing Services
Emergency & planned · RG40
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Glow-worm Specialists · Gas Safe 599015 · 130+ reviews
Glow-worm issue? Call Stuart.
Gas Safe 599015 · £96 fixed diagnostic · Annual service from £96 · F75 specialists · Calls answered 24/7