High
Low water pressure on Keston Combi 30

Your boiler has detected that the water pressure inside the heating system is too low to run safely, causing it to shut down temporarily.

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.

What the manual says

Manufacturer manual

1 fill system to 1.0 bar - 2 Bleed radiators - 3 Contact installer

From this model's manual
Verified against the Keston/Keston 30c installation & service manual, page 17.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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Related fault codes

E01View →E02View →

All 32 fault codes on the Combi 30

Seeing a different code? Every code this model can display, in one place.

818283848586878889909192939495BCC FaultFalse Flame LockoutFan FaultFlame LossFlow Temperature Overheat LockoutFlow Thermistor FaultIgnition LockoutLow mains voltageNo water flow lockoutOutside sensor faultOverheat lockoutPCB FaultReset the boilerReturn Thermistor FaultReturn Thermistor Fault (No water flow)Too many resets

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