BoilerFaultCodesYour boiler has stopped working because the water pressure is too low for it to operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Fault F22 will be stored in the fault list if the water pressure falls below 0.03 MPa (0.3 bar).
What causes this fault?
This fault occurs when the water level inside your central heating system drops too low for the boiler to function safely. The most common reason is a slow leak from a radiator valve or a pipe joint, but it can also happen if you have recently bled your radiators without topping the water back up.
This fault is frequent in autumn when homeowners turn their heating back on for the first time and discover pressure has dropped over the summer months.
DIY fix possible
Locate the filling loop handles (usually two blue or black taps) underneath the boiler.Slowly turn both handles 90 degrees to allow water into the system while watching the pressure gauge.Close both handles fully once the pressure reaches between 1.0 and 1.5 bar.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like F22 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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