What's causing my boiler to lose pressure

Joined
15 Jul 2008
Messages
14
Reaction score
0
Location
North East
Country
United Kingdom
I've recently noticed that the pressure gauge on the boiler was showing zero, (heating, and hot water appears to be fine) when changing the timing of the boiler.

Checked all radiators to see of their is any signs of leaks - there is none.
I increased the pressure to 1.5 bar using a filing hose.
After a few hours - the pressure increased to over 2.5 bar.
A further few hours it has now decreased back to zero.

Outside of the house, I have noticed the copper pressure relief pipe has been dripping.

What's the cause of the boiler losing pressure ?

Could it be that it's not actually losing pressure.

It has just been serviced recently - but assume that this problem is just a coincidence that it's occurred shortly after the servicing.

I am assuming that it's faulty gauge - and that by me adding more pressure to the boiler (altough appearing to just rise to 1.5 bar is actually increasing beyond, thus causing the pressure relief pipe to show signs of dripping.
 
Sponsored Links
Joined
4 Oct 2012
Messages
9,114
Reaction score
2,702
Location
East Renfrewshire
Country
United Kingdom
If it was service recently, I'd be phoning and asking them to have a look on the back of that service, especially whether they checked the Expansion Vessel and its pre-charge. The PRV may need to be looked at too now.

How old is the boiler?
 
Joined
21 Sep 2015
Messages
3,489
Reaction score
902
Location
Wiltshire
Country
United Kingdom
If it was serviced recently then a check on the safety device ( prv ) would of been carried out , not something I do for this reason
 
Joined
15 Jul 2008
Messages
14
Reaction score
0
Location
North East
Country
United Kingdom
If it was service recently, I'd be phoning and asking them to have a look on the back of that service, especially whether they checked the Expansion Vessel and its pre-charge. The PRV may need to be looked at too now.

How old is the boiler?

Boiler is approx 10 years old...

When I mentioned that a service had been done - this was a visit to see if the boiler could be placed on a Homecare service plan.

I assumed this was also a service visit.
 
Joined
21 Sep 2015
Messages
3,489
Reaction score
902
Location
Wiltshire
Country
United Kingdom
Boiler is approx 10 years old...

When I mentioned that a service had been done - this was a visit to see if the boiler could be placed on a Homecare service plan.

I assumed this was also a service visit.
You assumed wrong
 
Joined
4 Oct 2012
Messages
9,114
Reaction score
2,702
Location
East Renfrewshire
Country
United Kingdom
Notorious fault with PRV's when they are activated after a long period but they are usually cheap to replace if they then pass.

The drop to 0 and then filled to 1.5 and rise to 2.5 and then back to 0 when cooling is a classic expansion vessel issue which should also be checked at service time, an empty or bust EV would probably have caused the PRV to activate and continue to do so every time the system is topped back up.

It needs serviced as it wouldn't have been done with that visit.
 
Joined
15 Jul 2008
Messages
14
Reaction score
0
Location
North East
Country
United Kingdom
You assumed wrong

Just sent an email of to my utilities supplier for them to confirm whether or not this was a service visit.

If it wasn't - will arrange for a service - and hopefully the fault will be rectified.
 
Sponsored Links
Joined
4 Oct 2012
Messages
9,114
Reaction score
2,702
Location
East Renfrewshire
Country
United Kingdom
Yep, it should do, one way or another.

It can one of 2 ways but should be sortable. Either an easy sort out and resetting of EV and run the PRV a few times and hope it seals back up or a more expensive piece of work to replace the vessel and valve.
 
Joined
4 Oct 2012
Messages
9,114
Reaction score
2,702
Location
East Renfrewshire
Country
United Kingdom
Heh, with regards to giving the OP advice on their issue @Stadan20 , I can't really see how being a GSR engineer would have anything to do with correctly diagnosing a non gas related item like a failed/empty EV by a boilers pressure behaviour or knowing an older PRV can pass when activated especially on an older boiler??

That being said, OP, I am happy to confirm I am GSR :rolleyes:
 
Joined
21 Sep 2015
Messages
3,489
Reaction score
902
Location
Wiltshire
Country
United Kingdom
Heh, with regards to giving the OP advice on their issue @Stadan20 , I can't really see how being a GSR engineer would have anything to do with correctly diagnosing a non gas related item like a failed/empty EV by a boilers pressure behaviour or knowing an older PRV can pass when activated especially on an older boiler??

That being said, OP, I am happy to confirm I am GSR :rolleyes:
Op hasn't confirmed the boiler , and I haven't seen you on the combustion chamber , also I like winding people up ......
 
Joined
4 Oct 2012
Messages
9,114
Reaction score
2,702
Location
East Renfrewshire
Country
United Kingdom
Nope, not confirmed the boiler type 4 sure but never like to assume that at 10 years it's very possible to have a sealed CC

Been in the CC, is a good idea, some nice guys, some excellent chat/advice but like everywhere there are a few zoomers

yeah...me too ;)
 
Sponsored Links
Top