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Glow-worm specialists across Wokingham · Arborfield · Earley · Woodley · Finchampstead · Shinfield · Winnersh · RG40 · RG41

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Glow-worm specialists · Gas Safe 599015 · F75 experts · Wokingham & RG40

Glow-worm Boiler Support — Wokingham

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.

Book Online 24/7 Call 07850 116944

£96

Service &
diagnostic

90%

First-time
fix rate

Same day

Where
available

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Need Glow-worm help today?

Repairs · Servicing · Fault codes · RG40

Annual serviceFrom £96

Diagnostic fee£96 fixed

First-time fix90%

Book Online 24/7 07850 116944

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.

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 →

View full fault code 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) →