Logic Combi 35 losing pressure

[geordiepaul2001]

Hi folks,

I'm a customer who has a 3 year old Logic Combi 35 in my house that has been losing pressure regularly since the new year.
At first it was every 3/4 days but I tried adding a leak inhibitor which delayed it to every 7 days, but after a couple of week it returned to every 3/4 days.
There is no signs of a leak on the walls or ceilings, the valves are dry, there is no air in the radiators and I have had a bottle over the PRV and it is bone dry.
Whilst away on a short holiday I was able to isolate the boiler for five days and the pressure did not drop.

We only have one pipe running underground (a garage conversion) and this pipe has now been capped off. The result of doing this is that the boiler is now losing half a bar of pressure every 6/7 days, so it has slowed the leak quite a bit.

It is driving me mad because I can't find a leak anywhere, the heating engineer serviced the boiler and said it was fine and all of the radiators etc aren't showing signs of leakage.

Any ideas or strategies for finding the leak?

Paul

 

[king of pipes]

Beware bud ideal have had problems with their heat exchangers you could be losing pressure through there when it's hot you wont see it because it will drain through the condense get your installer back to check it out if it has failed the warranty period is 7 years so it should be replaced free by ideal make sure your service records and benchmark are complete , I had a 24kw logic fail and I know of a 35 kw locally to me fail hope this helps regards k.

 

[geordiepaul2001]

Ah okay I thought I had ruled out the boiler and it's associated parts when I isolated it prior to our holiday. I thought that as it hadn't leaked, then the issue with within the central heating side of things.

I have just checked and my boiler is only covered by a two year warranty unfortunately.

 

[Scott_D]

Sounds like a system leak to me. increase the pressure to 2.5 bar and look for any wet bits
It may only leak when the heating is on and things are warm

 

[ShaunCorbs]

System leak could be anywhere tbh

 

[geordiepaul2001]

Would there be any reason why the leak would slow so much once one section is capped off?
Also, in these situations is it better to go through my home insurance for track and trace, or to get my boiler tech to cap off pipework until we find it?

As I imagine most people are, I'm trying to keep the costs to a minimum.

 

[geordiepaul2001]

Would there be any reason why the leak would slow so much once one section is capped off?
Also, in these situations is it better to go through my home insurance for track and trace, or to get my boiler tech to cap off pipework until we find it?

As I imagine most people are, I'm trying to keep the costs to a minimum.

 

[ShaunCorbs]

Would there be any reason why the leak would slow so much once one section is capped off?
Also, in these situations is it better to go through my home insurance for track and trace, or to get my boiler tech to cap off pipework until we find it?

As I imagine most people are, I'm trying to keep the costs to a minimum.

yea could be the leaks were further down that leg of the pipework and theres a few pin holes remaining

i would pressure test the system first with the boiler isolated to see how much / if theres any drop and go from there

 

[huddster]

I'd put money on the heat exchanger, pretty sure the isolation valves and pressure gauge are on the system side not the boiler, so if holding pressure when isolated system would be ok. I'd double check first then repeat the test.

 

[bazzlar]

How often are you filling the system ?

 

[geordiepaul2001]

Hi all,

Apologies for the delayed reply.
I've had another engineer look at the boiler and he has said that it's the heat exchanger at fault.
He said that he cranked the pressure up and it is leaking into the consense, as suggested above.
He also said that it was 'sludged up'.

I'm not sure where I would stand trying to argue with Ideal, I would expect a boiler to last longer that a few years before developing faults.

Paul

 

[townfanjon]

Paul , them heat exchanges are useless , its well documented that Ideal are having problems with them .

House next to where I am working at the moment is having the same problem

 

[bazzlar]

Have you checked the pressure in the expansion vessel and that it is not passing through the pressure relief valve.