Recent: Trayford close coupled toilet?

Mend Ariston Home Heating Systems

Mend Heating, Home Heating Systems
Find out how to mend it for free.

Ask Question
Mend Heating, Home Heating Systems
Click here to mend Ariston home heating systems

Mend > Home Heating Systems

Mend Heating, Home Heating Systems

What is causing my Ariston boiler microsystem 21RFF1 to gain pressure ?

What is causing my Ariston boiler microsystem 21RFF1 to gain pressure causing the safety valve to open and shuts the boiler down - not due to overheating.

John Shailer
November 2008
I have changed the expansion vessel and it is now working perfectly

John
November 2008
There are several things that can cause this problem, does the pressure increase when the boiler is not in use? if so maybe the filling loop is letting by or your water to water heat exchanger has failed, try disconnecting the filling loop and check if the pressure still increases. If the problem is when the boiler is running then it could be your expansion vessel has failed or just needs to be re-pressurised (with air).

Martin
November 2008

Automatic Answer

While you wait for answers, we may have found some information which could help you.

Click here for Causing Pressure Valve

Mend Heating, Home Heating Systems
Click here to mend Ariston home heating systems

How to mend ...

Find out how to mend just about anything howtomendit.com for free repair help, information and advice.
Mend Heating, Home Heating Systems
Click here to mend Ariston home heating systems