Odd boiler pressure issue

[Ali Ahmed]

I have a 2yr old Ideal Logic C35 boiler which is losing pressure 5 to 6 times a day. To diagnose whether it was the boiler or system, I done the following:
1 At 1am when the boiler hadn't been used for over 2hrs, I put the pressure upto 2 bars.
2 I isolated the boiler by turning the CH flow and return pipes and cold water pipe.
3 Switched the boiler off at mains.
4 Put a bag/bowl aroud the prv and condense pipe to collect ang water.
In the morning the boiler pressure dropped to zero but absolutely no water from either pipes. A gas safe engineer who was advising me over the phone said its really srrange and there was nothing he could do. I contacted Ideal Logic and they said it was strange that no water is leaking. The advised to book their engineer for a fixed price repair of £295.00 whatever the fault. Before I take the plunge in these hard times, does anyone have any ideas as to what the problem might be?

 

[CBW]

If you isolated the boiler, didn’t use it at all overnight and it dropped, possibly leaking down the condense pipe, best leave it to Ideal for the fpr.

 

[Ali Ahmed]

If you isolated the boiler, didn’t use it at all overnight and it dropped, possibly leaking down the condense pipe, best leave it to Ideal for the fpr.

I put a bowl around the condense pipe and the was no water leak

 

[CBW]

Well it’s going somewhere

 

[MeldrewsMate]

...I isolated the boiler, put a bag/bowl aroud the prv and condense pipe, pit up the pressure to 2 bars and switched the boiler off overnight...

Hmmm. How did you pit up the pressure if the boiler was isolated?
And what was the boiler temperature when you switched it off? Hot? Cold?
Did you also isolate the cold mains water inlet to this combi boiler?

Please remove the ambiguities and post clearly what you did, and in what order.

 

[Ali Ahmed]

Hmmm. How did you pit up the pressure if the boiler was isolated? PRessure up to bars and then immediately isolated.
And what was the boiler temperature when you switched it off? Hot? Cold? Cold, I dis it at 1am-at least an hoir after last use
Did you also isolate the cold mains water inlet to this combi boiler? Yes

Please remove the ambiguities and post clearly what you did, and in what order.

 

[terryplumb]

What exactly did you do to " isolate" the boiler ?
I suspect you have not isolated the boiler from the flow and return pipework ,and you have a leak on your system.

 

[MeldrewsMate]

And did anyone use or try to use any hot tap during this test period?

 

[MeldrewsMate]

Suggest you repeat the test tonight...

1. Start with a cold boiler.
2. Top-up to 2 bar.
3. Isolate ONLY the heating flowand return pipework.
4. Switch off the boiler.
5. Review in the morning

 

[Ali Ahmed]

And did anyone use or try to use any hot tap during this test period?

No, not until 7.30am when I swithed the boiler back on.

 

[Ali Ahmed]

What exactly did you do to " isolate" the boiler ?
I suspect you have not isolated the boiler from the flow and return pipework ,and you have a leak on your system.

The gas engineer told me which pipes to turn off. They are coloured so its easy to identify.

 

[terryplumb]

Boiler isolation valves are notorious for not fully closing. You have a leak on the system side.
Do you have any of your central heating pipes either buried in concrete ,or under flooring anywhere ?

 

[Ali Ahmed]

Suggest you repeat the test tonight...

1. Start with a cold boiler.
2. Top-up to 2 bar.
3. Isolate ONLY the heating flowand return pipework.
4. Switch off the boiler.
5. Review in the morning

Thanks, will do. Message back in the morning.

 

[Ali Ahmed]

Boiler isolation valves are notorious for not fully closing. You have a leak on the system side.
Do you have any of your central heating pipes either buried in concrete ,or under flooring anywhere ?

Yeah, most of the pipework is buried under floor or walls.

 

[terryplumb]

I assumed so.