Firebird Oil boiler, pressure always increases....?

[JamesJ]

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

 

[kevplumb]

you / your plumber have of course disconnected the filling loop

 

[Dick Puller]

Has he disconnected the filling loop?? Sorry to say this but I fear you employed the services of a unqualified Plumber, there's many CC/CCCs about.
CC = Course Cowboy
CCC = Career Change Chancer

They are failed this or that, have a mid life crisis & go on a 4 week Plumbing course. Can't get jobs, so set themselves up a self-employed Plumbers & rip off the general public.

 

[sooey]

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.

Surely to christ anyone who does the above is not going to be thick enough to leave the filling loop connected.

CCC = ************

 

[sooey]

Could've at least left the Crusty Caledonian bit in.

 

[JamesJ]

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

 

[WDIK]

the vessel connectin to the system is blocked

 

[leakydave]

Come on guys... is the heat exchanger for the COMBI leaking? I have seen this on two different boilers. Should get it replaced under warranty.

And these CC and CCC chaps.... we were all beginners once!

 

[doitall]

I would say the heat ex is pin holed. I assume it uses a plate hx.

Next time it get high turn the mains off and open the hot taps to see if it drops, you may see the pressure fluctuate by opening a closing the kitchen tap.

 

[snb]

correct the pressure and then remove the filling loop. if the isolating valve is damaged it will continue to leak.

if this doesn't leak and the pressure continues to rise then it is likely to be the DHW plate exchanger has failed.


I have experienced problems where there has been 2 filling loops. (another hidden behind kitchen cupboards after refurb that was letting by slightly)

 

[holty]

as youve mentioned youve already disconnected the filling loop. id go for the plate heat ex being pin holed.try what doitall has suggested.also id get someone in who knows what a plate heat ex looks like.by sounds of it the last plumber doesnt know how a heating system works.

 

[JamesJ]

cheers guys, i spoke with another plumbing who we've used in the past and he told me to take off the expansion vessel, turn it upside down and to press the valve in and guess what, water came out. i beleive this is the problem? sounds like a need a new one.

 

[Paffman]

...he told me to take off the expansion vessel, turn it upside down and to press the valve in and guess what, water came out. i beleive this is the problem? sounds like a need a new one.

So the first guy didn't check the exp vessel dry side pressure after all