condensing boiler leak

[JBaill]

I'm losing pressure in my wet underfloor heating system but have no sign of leakage. However I have noticed that the condensate drain line from the boiler has a flow of around 70 drips per minute and probably fills a pint jug in 5 or 6 hours. Is this normal or could this be the source of the leak across the condenser heat exchanger? I'm not sure how much liquid drop out is normal. This line is purely for the condensor and not the safety valve which seems to be holding OK. Condensate just looks like warm water and wouldn't imagine that much moisture in the air. It is a large system covering 300M2.
Any thoughts would be helpful.

 

[oilman]

. Condensate just looks like warm water and wouldn't imagine that much moisture in the air.

It's not moisture in the air, it's water formed by the combustion of hydrogen in the fuel. I presume the fuel is gas, but you haven't said if it is, nor what boiler you have.

 

[blondini]

Do be careful 007.
The duplicate thread (locked) had helpful replies.
//www.diynot.com/forums/viewtopic.php?t=175022

 

[Agile]

I dont know why you dont want to tell us the boiler make and model!

Its easy to see if there is a leak from the boiler!

Leave it switched off with the system pressure set to 1.5 Bar and put a bottle on the condensate output for a few hours or overnight.

Obviously with the boiler off there will be no condensate produced so any water that continues to come out will be a leakage from the heat exchanger.

Have you first checked your PRV vent is not leaking?

Tony

 

[Agile]

Do be careful 007.
The duplicate thread (locked) had helpful replies.
//www.diynot.com/forums/viewtopic.php?t=175022

Looks like Mad Mod 7 locked the posting with the replies and left this one.

With no replies he would have been better to just delete the unanswered duplicate which was presumably posted by mistake.

 

[JBaill]

Model is Geminox distributed under the name of Yorkpark (9 years ol). It's a natural gas fired model.

 

[JBaill]

PRV seems to be OK and is totallt separate

 

[Agile]

Model is Geminox distributed under the name of Yorkpark (9 years ol). It's a natural gas fired model.

The brand name of the manufacturer is Geminox!

We dont know the model yet!

Tony

 

[JBaill]

Not at home just now but sure its THR 5/25

 

[Agile]

Its easy to see if there is a leak from the boiler!

Leave it switched off with the system pressure set to 1.5 Bar and put a bottle on the condensate output for a few hours or overnight.

Obviously with the boiler off there will be no condensate produced so any water that continues to come out will be a leakage from the heat exchanger.

Tony

 

[simond]

Isolate off the UFH at the manifold valves for a day or so and see if the pressure still drops.

Many manifolds have a pressure gauge for you to monitor (bear in mind if the screed is warm the pressure will drop slightly as it cools).

 

[JBaill]

Thanks for the reply. This is what I'm finding when I isolate at the manifolds. It is a big volume covering 300M3 so I do still get some contraction as the concrete floor cools down.

 

[Agile]

I would say that you should isolate at the boiler if you must!

But only do that when the system ( floor ) is already cooled down.

My rough guess makes the system volume less than 60 litres or less that a conventional rad system but I might have made an error.

Tony

 

[JBaill]

Problem solved. My wife found a brown stain yesterday on the ceiling. Turned out that the leak was in this area. On investigation, a nail had been hammered through the plastic pipe 9 years ago when the house was built but had sealed around the plastic. After 9 years the nail turned to a small piece of rust and had a catastrophic failure. Luckily all repaired and only slight mark on ceiling to be painted. Unfortunately I was off the North East coast of Russia when it all happened................
Any comments on these Geminox boilers? British gas coming next week to inspect for a maintenance contract as it is now on their list. Not sure if I should consider getting a new one fitted.