Low Water Pressure
The boiler's water pressure has dropped below the safe minimum level. One of the easiest faults to fix yourself.
Step-by-Step Fix Guide
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Step 1
Turn the boiler to OFF
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Step 2
Locate the filling loop under the boiler (internal key type or external flexible hose)
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Step 3
For internal key type: turn the key anticlockwise to open the valve
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Step 4
For external loop type: open both small valves slowly
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Step 5
Watch the pressure gauge and stop when it reaches 1.0–1.5 bar (green zone)
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Step 6
Close the valves or turn the key back
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Step 7
Turn the boiler back to heating mode
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Step 8
If pressure drops again within days, you may have a leak — contact a Gas Safe engineer
Work on gas appliances must be carried out by a Gas Safe registered engineer. The steps above cover safe checks a homeowner can perform - any internal component replacement requires a qualified professional. If in doubt, always call an engineer.