What does Potterton E20 mean?

Central heating sensor fault, or the boiler has overheated.

How do I fix Potterton E20?

Try first: Check the pressure gauge reads about 1–1.5 bar; Bleed your radiators to clear trapped air; Press reset once. If that doesn't clear it, the likely part is Temperature sensor.

Potterton E20 Fault — What It Means & Fix Cost

⚠ This is the likely cause from the code — a Gas Safe registered engineer confirms it on site. If you can smell gas, stop and ring 0800 111 999.

✅ Try these first — they're free

Often clears it without a callout:

Check the pressure gauge reads about 1–1.5 bar
Bleed your radiators to clear trapped air
Press reset once

🔧 If that doesn't fix it

The likely cause is one of these — the engineer confirms which:

Most likely part: Temperature sensor

What it costs

Fixed price,
no callout fee

Free diagnosis first, then one fixed price for the repair — you only pay if you go ahead.

A vetted Gas Safe engineer who covers your postcode will call you back to arrange the repair. No callout fee — you only pay if you go ahead.

Other Potterton fault codes

Potterton E09Gas valve wiring or connection fault.…Potterton E10Outdoor (external) sensor fault.…Potterton E109Poor circulation around the system.…Potterton E110The boiler has overheated and tripped — often a stuck pump o…

Potterton E20 — what it means

✅ Try these first — they're free

🔧 If that doesn't fix it

Other Potterton fault codes

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