Hello Firebird,

We have a Firebird Combi 90 and a few weeks ago we had thermostats put on our radiators and the water pressure in the system was refilled to the correct level of 1-1.5 bar when cold. For a few days everything was fine and then the pressure in the system increased in to the red, to about 3 bar. The safety valve outside is functioning fine and is releasing water, but pressure is staying in the red still.

The radiators have been bled a few times with no or little effect and the pressure keeps rising to the same level.

The plumber that fitted the thermostats has been back a number of times, he drained the system and adjusted the the pressure in the expansion chamber to make sure it was correct (I think thats what he did) and then put the water back in to the correct pressure, but then again the next day the pressure increased to 3 bar.

Yesterday he came out and took two of the radiator thermostats off (that he originally put on, one upstairs and one downstairs), he believes that would fix it, but hasn't.

Does anyone have any ideas on what the problem might be?

Many thanks

JamesJ

JamesJ, September 2009

hi guys, the filler loop is disconnected, and i've drained the system back to 1-1.5 and next morning its still bacl to 3. the latest is that the plumber came out last week and took two of the thermostats off as he thought the hot water in the system had now where to go, but the pressure still increase to 3. yesterday he thought we would have to just take all the thermstatic valves off, and this morning we are back to 3.

i am fuming, we have no valves on the radiators and are back to square one, a fair bit of cash out of pocket, and the pressure is still at 3 :-(

JamesJ, October 2009

Remove your filling loop. Be carefull because it sounds like it's passing.
If pressure keeps going up it'll be because the plate heat exchanger is passing. New exchanger required.

M, September 2009

turn off filler valve to heating system, drain pressure back to 1bar,run system as normal,if pressure holds then filler valve may need adjusting/ replacing. check pressure in expansion.

t.m, September 2009

I think that your filling loop is leting by you should dis connect it to make sure, David

capitalboilers.co.uk, September 2009