Potterton Boiler Error Codes: Full UK Guide (2025)
Complete UK breakdown of Potterton boiler fault codes — causes, fixes, and typical repair costs for Gold, Promax, Titanium, Profile and older models.
Potterton Boiler Error Codes: Full UK Guide (2025)
Potterton boilers — including the Gold, Promax, Titanium, Profile, and older Suprima models — are common across UK homes in London, Birmingham, Manchester, Liverpool, Leeds, Bristol, and Glasgow.
This comprehensive guide explains every major Potterton error code, what it means, how to fix it, and typical UK repair costs for 2025.
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Most Common Potterton Error Codes
E133 – Ignition Failure (Very Common)
The most frequent Potterton fault in the UK.
Meaning: Boiler attempted to ignite but failed.
Causes:
- Frozen condensate pipe (winter issue)
- Faulty ignition electrode
- No gas supply
- Blocked burner
- Gas valve fault
Fix:
- Thaw frozen condensate pipe
- Check gas supply and meter
- Reset boiler
- Engineer: check electrode and gas valve
Typical UK Cost: £120–£320
E125 – Overheat / Blocked System
Meaning: Temperature too high.
Causes:
- Pump failure
- Blocked heat exchanger
- System sludge
- Airlock
Cost: £150–£350
E117 – Low Water Pressure
Common after bleeding radiators or with system leaks.
Fix:
- Repressurise to 1.0–1.5 bar
- Check for leaks
- Bleed radiators
Cost: £0–£160
E1 – PCB Fault / Communication Error
Control board cannot communicate properly.
Fix: Engineer required to diagnose and replace PCB.
Cost: £250–£480
E3 – Fan Speed Fault
Meaning: Fan not reaching correct speed.
Fix: Replace fan assembly.
Cost: £180–£350
Additional Potterton Fault Codes
E119 – Low Pressure (Similar to E117)
System pressure below safe level.
Cost: £0–£150
E128 – Flame Loss
Causes:
- Low gas pressure
- Faulty flame sensor
- Burner debris
Cost: £120–£280
E118 – Air Pressure Switch Fault
Flue or air intake issue.
Cost: £140–£300
E160 – Internal Fault
Requires engineer diagnosis.
Cost: £120–£280
E110 – Overheat Thermostat
Safety lockout due to overheating.
Cost: £140–£300
Potterton Gold & Promax Specific Issues
The Potterton Gold and Promax ranges commonly show:
- E133 during cold weather (frozen condensate)
- E125 when pumps fail or systems become blocked
- E1 on older models with failing PCBs
Frozen Condensate Pipe (UK Winter)
Many Potterton faults (especially E133) occur when external condensate pipes freeze.
Fix:
- Pour warm (not boiling) water over the pipe
- Reset boiler once thawed
- Insulate the pipe to prevent recurrence
Cost: £0–£80
Potterton Boiler Repair Costs (UK 2025)
| Fault | Typical UK Cost |
|---|---|
| Low pressure (E117/E119) | £0–£160 |
| Ignition fault (E133) | £120–£320 |
| Overheat (E125/E110) | £150–£350 |
| Fan replacement (E3) | £180–£350 |
| PCB replacement (E1) | £250–£480 |
| Flame sensor (E128) | £120–£280 |
| Pump replacement | £180–£350 |
| Annual service | £70–£90 |
London and South East costs typically 10–20% higher. Midlands and North West usually cheaper.
When to Call a Gas Safe Engineer
You MUST call a Gas Safe registered engineer if the issue involves:
- Gas valve
- PCB or control board
- Internal fan
- Burner assembly
- Flue or combustion issues
- Any internal components
Never attempt DIY repairs on gas-related components.
Stay protected year-round:
Should You Repair or Replace?
Consider boiler replacement if:
- Boiler is 12+ years old
- Repeated E133 or E125 faults
- PCB replacement needed on older model
- Multiple components failing together
- Repair costs exceed £500–£600
For peace of mind and protection:
Final Advice for UK Homeowners
Potterton boilers are reliable but commonly show faults like E133, E125, and E117 — especially during UK winter when condensate pipes freeze and system pressure drops.
To minimize breakdowns:
- Get an annual boiler service
- Maintain correct system pressure (1.0–1.5 bar)
- Insulate external condensate pipes
- Address pressure drops quickly
Protect your home with: