Mend > Home Heating Systems

Mend Ariston Micro Combi 23mffi Boiler Heating

High pressure in Ariston microcombi boiler?

My Ariston Micro Combi 23mffi keeps rising up to 2.7 bar. I have drained the system to let it fall back to 1.7 but it climbs back up over about a day or two. It never gets higher than 2.9bar, but I am worried about it bursting a pipe when I put the central heating on. Any ideas of how to remedy this, there doesn't appear to be any way of decreasing the pressure into the boiler from the cold inlet short of turningback the inlet tap.

Nigel Bates
September 2005

Ariston Ariston Micro Combi 23mffi Heating, Home Heating Systems Boiler Heating Combi

either filling loop on or expansion vessel in boiler full of water where it should be half water and half compressed air

gasman2007
September 2007

some problem on my combi boiler...although its a Baxi.
domestic heat exchanger was leaking water into the central heating system. This is the only point where the hot water and heating systems meet. Once fixed, recommend that you treat your c/h with an anti corrosion product if not done already.

approx 60 to replace.

scott
November 2006

should the filling loop be fully closed all the time?....is this the silver flex pipe providing cold water to the boiler??

andrew
March 2006

Filling loop letting by/not fully closed
or (worst case) leak in the secondary heat exchanger

RS Plumbing
November 2005