Core Diagnosis: Most boiler pressure loss is caused by a failed expansion vessel or a passing PRV, not visible pipe leaks.
Local Factor: Leicester’s hard water accelerates scale buildup inside vessels and valves.
Resolution: Recharging may work short-term; PRV or vessel replacement is often required.
Rule of thumb: If you are topping up your boiler more than once a month, something has failed. Boilers are sealed systems — they do not consume water in normal use.
In Leicester homes, the most common causes are a failed expansion vessel or a passing pressure relief valve (PRV).
Leicester has hard to very hard mains water. Over time, limescale builds up inside expansion vessels and valves, preventing them from regulating pressure correctly.
In areas such as Clarendon Park, Highfields, and Oadby, heating systems are often older and less tolerant of repeated pressure changes.
| Symptom | Likely Cause | Typical Fix |
|---|---|---|
| Pressure drops when heating is on | Expansion vessel lost charge | Recharge or replace vessel |
| Water dripping from copper pipe outside | PRV passing | PRV replacement |
| Pressure drops overnight | Slow system leak | Leak detection & repair |
Systems that are regularly topped up often suffer radiator and pump failure within a few years.
Our Gas Safe engineers diagnose pressure faults properly — no guesswork.
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