Pressure Drop Again...

[Syd98]

Hi.
We have a sealed unvented megalo with an ideal minimiser boiler which are both 10yrs old. Last winter we had a problem with dropping pressure, We had 3 x local corgi plumbers to look at the system, between them they changed auto vent, expansion vessel and the pump, i have also had all the floor boards lifted and pipe work checked for leaks etc etc. All TRV's are also working well.
This did not cure the problem but for some "strange reason" the problem then righted itself, all over the summer the pressure as been good at 1.5bar.
Now the heating is working again with the cold snap the pressure is now dropping everytime we run the heating for more than two hours.

Presummably the problem is within the boiler and the heat exchanger and now the boiler is working hard again the problem is back.
I have checked within the boiler and there is no water etc etc and collecting the water from the drain does not appear to be anything other that usual condensation etc.

Has anyone else experienced this problem. If the boiler requires replacing how good are the worcester greenstar range.

Thanks. any suggestions appreciated apart from it's a leak mate..!

 

[superdupergasman]

Has some internal leak sealer been added to the system??

I always use the salemander range, its NEVER let me down....yet!!!

When the system is topped up to 1.5bar then run on CH what does the needle go up to??

Has the saftey relief valve been changed??

Has the pipe going to the expansion vessle from the boiler been checked for blockages??

Worcester greenstars are not bad...have a look at vaillant and viessmann
the latter you can get some good warrantys with if you use an approved installer.

 

[Deleted member 105431]

put a balloon over the prv pipe outside and check if it fills with water. The minimiser heat exchanger may be leaking in which case it's new boiler time. If you do get a new boiler Vaillants are very good quality and the ecotecplus 600 or 400 would be ideal.