High
LOW WATER TEMPERATURE on Potterton Main Mersey Super

Your boiler is struggling to heat the water to the correct temperature because there is an issue with how it manages its internal gas flow.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

1. Gas pressure too low. 2. Faulty diaphragm. Will also cause a high water rate. 3. Automatic gas valve push rod sticking. May also cause a high water rate. 4. Slow ignition screw incorrectly set. Will also cause a high water rate.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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