Why is my central heating system losing pressure?
Why is my central heating system losing pressure? A boiler that keeps losing pressure is therefore always cause for concern. There are two main problems that typically cause a loss of pressure - water escaping somewhere in the system or a failure of the expansion valve and resulting damage to the pressure relief valve. Can boiler pressure drop without a leak? Is Your Boiler Losing Pressure But There's No Leak? In 99% of cases, a boiler losing pressure means a leak — it's as simple as that. Unless the dial sits at 0 even when topped up (which could be...