IVT Hidden System Leak / Micro-Leak

Boiler loses pressure over time without visible leaks

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Leak under floors or in walls, Leaking plate heat exchanger to DHW side, Slow seep from safety valve, Air vent weeping intermittently

Safety: Repeated topping up introduces fresh oxygen and can damage the boiler. Do not ignore ongoing pressure loss.

Steps:

Check the pressure relief valve discharge pipe outside for signs of dripping.
Inspect all radiators, valves, and visible pipework for staining or damp patches.
A technician can isolate the DHW side and test for a leak through the plate heat exchanger.
For hidden leaks, a pressure test and tracer dye or thermal imaging may be required.

Hard 4/5

Pressure Relief Valve

Check Price on Amazon

We may earn a commission from links on this page.