My boiler has been losing pressure for some time. It only appears to lose pressure when the central heating is on and not when using the hot water.
The pressure gauge also appears to be faulty, it is stuck on 1.2 bar most of the time but does creep up to about 1.4 bar when the heating is on.
I am having to top it up daily now.
Am I correct in assuming that the expansion vessel is faulty, if so how difficult is this to change.

Terry Duffy, January 2010

Check the pressure in the expansion vessel if it is not at 1 bar then water will be thrown out of the pressure release pipe

Just passing through, April 2011

the boiler keeps kicking in out after around about minute and a half but shortly after kickes back in i have done everythink tht you said about pressuring the expansion vessel to 1 bar. all i did was drain the upstairs system to take a bathroom radiator off and put it back on could u see if anythink else could be the problem

scott, November 2010

I have exactly the same boiler and have had the same problem for months now. (Although no sticky pressure guage) Could not find any leaks anywhere and the plumber was baffled as to what the cause was. Finally last tuesday the expansion vessel blew - obviously where there water was leaking from - in spectacular fashion. Apparently Ferrolli are waiting for a shipment and dont know when they are going to be in so i still have no heating/hot water still so id order a new one now if i were you! Check to see if any water is leaking from the bottom right hand side of the boiler.
Think this is a cheap nasty boiler. Out of interest the dials that control hot water and heating temp....mine just turn without any end stop and just produce random wildly fluctuating numbers in the display window. Do you also have this problem? Seems impossible to set a temperature for either water or heating!!
Sorry to be the bringer of doom and gloom, hope it was of some help though!

Darren B, February 2010

first check for leaks on rads and pipework and vent rads to eliminate.then the cause is ablocked hole on the gauge and sometimes a needle can unblock them ,and the expansion vessel will need recharging to 1 bar with a foot pump

ferrroli engineer, January 2010

check the pressure relief valve outlet its the pipe that comes out of the wall outside it may be passing water only when the pressure increases above 1.4

brian, January 2010

The pressure gauge is only for the heating and not hot water. The pressure will always rise when heating is on as temperature and temperature are linked.I wouls suggest that you have a leak somewhere on your heating system. maybe it is leaking a little under the floor boards.is the neddle on your pressure gauge wobbling a little as this could indicate that your expanssion vessel is faulty.

tyemanone, January 2010