PROMAX COMBI HE PLUS A - PRESSURE ISSUE

[andrew171]

Looking for thoughts so i don't get ripped off etc by engineers.
Hi all, as per tittle "Condensing combination boiler".
Recently the water pressure guage is hovering on green max2 and red3 for excess pressure, our water meter is not spinning so no water is running.
1.open the relief valve drain down the excess pressure to about 1 on the guage and close, then it varies: 10secs or 3mins the pressure returns back to max2 sliping into red3 and upwards on the pressure guage.

2. hot and cold water supply is good and good temperature but this high pressure is a concern.

There is no damp external water leaks, the water meter is not spinning so assume no water is being drained off due to leakage, so why a pressure increase? .....

Reading on here a faq: mentions a perforated heat exchanger? are there any simple checks we can do ourselves.

I intend to also access the expansion vessel, when I remove the cover and see what sort of pressure is currently in it using a Schrader pressure guage and compare to any label information on the side of the vessel etc.

Any views are greatly appreaited , cheers andy

 

[terryplumb]

i assume the pressure is increasing when the boiler is fired up and central heating on, and it does not increase when boiler is off. that is indicative of a problem with the expansion vessel . is the prv lifting automatically at around 3 bar ? you should not be doing this manually.

 

[andrew171]

Hi terry, cheers for reply, will sort out a small youtube clip, boiler is not operating no water being drained off burner is not firing to heat water etc so we open the exvess pressure tap to slowly pressure from red3 to green 1.5-2 and close tap and within secs on minutes the pressure is back to red3 an some times higher but currently not exceeding red 3.5, no water runing, no sink taps or toilet flush being used no radiator heat circuit turned on, no apparent heat or water movement etc but still this high pressure, will sort a video clip of whats happening, your views are appreaited. Being a qualified dealership technician i understand cars, so im trying to cover many simple checks before calling a plumber and not want to be taken for a ride with having xcess parts replaced? Good tradesmen are not easy to find not being in the plumbing trade we are in their hands, video to follow.

Again thankyou for your time and thoughts
Andy

 

[terryplumb]

just to clarify ,you are saying the pressure gauge ( or is it a digital one on your boiler ) is showing pressure increasing from 1 to 3 bar when the boiler is not even on ? the prv valve should open automatically around 3 bar and excess water should run out the relief pipework .if this is happening with boiler off it is nowt to do with expansion vessel. and more likely the cold mains is going into the CH cicuit. sounds more like the filling loop valve/s are partially open or the dhw heat exchanger is compromised .

 

[AGAS]

understand cars, so im trying to cover many simple checks before calling a plumber and not want to be taken for a ride with having xcess parts replaced? Good tradesmen are not easy to find not being in the plumbing trade we are in their hands, video to follow.

well you've probably made the cost of fixing your boiler more after your little fiddle with the PRV , no parts probably need anyway well might be lying , well you do now anyway.
stop fiddling

 

[durhamplumber]

Looking for thoughts so i don't get ripped off etc by engineers.

A great start!

 

[durhamplumber]

Being a qualifieddealership technician i understand cars......so garages never rip anyone off then...will you tell me for free how to mend my car?

 

[durhamplumber]

you have a very odd attitude...how do you like it when your car owners come in with that attitude!!.