Pressure fault
Boiler losing pressure? Repair across Somerset
If you're refilling more than once a month, water is leaving the system somewhere. There are only five realistic places it can go — we work through each one methodically until we find it.
For: Homeowners topping up the boiler every few days
The five suspects
Failed expansion vessel (pressure climbs then dumps via PRV), a weeping PRV itself, a leaking radiator valve, microbore under a floor, or a pinhole on the boiler heat exchanger. Each has a distinct signature and we test in that order.
What the diagnosis includes
- Expansion vessel charge tested and re-pressurised
- PRV outlet checked for weep
- Every radiator valve pressure-checked visually
- Thermal imaging on ground-floor pipe runs where useful
- Boiler internal seals inspected under working pressure
Frequently asked
- Can I just keep topping it up?
- Short term yes — but every top-up dilutes your inhibitor and accelerates corrosion. Fix the leak; don't paper over it.
- How long does the diagnosis take?
- 60–90 minutes typically. Under-floor leaks that need floorboards up take longer and we quote before opening anything.
- Is an expansion vessel expensive?
- Internal vessel repressurise is included in the visit. A replacement external vessel is around a mid-range service call — cheap versus a new boiler.
Book the diagnosis
Tell us how often you're topping up and any obvious wet patches. We'll come with the right test kit and fix on the first visit where possible.
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