valiant combi lost pressure, help!

17 May 2010
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United Kingdom
My valiant ecotec 831 boiler is only a few months old, need pressure topup everyday! My plumber hasn't a clue what is the cause! A valiant engineer has come and checked and he said the boiler is fine, suggesting that there is a leak in the system. I have done a pressure test to the boiler and noticed that while the boiler and the central heating are isolated 20 hours , the boiler itself dropped by .6bar. Does that mean the leaks is in the boiler itself not in the system.

I have checked the relief pipe and the bottom of the boiler, didn't see any leaks there. I have also checked the valves of all the radiators, no sign of leaks there either. I have checked all the ceiling, can't see any wet patches anywhere. Someone suggested that might suggested a fault in the heat exchanger, but how can I tell if this is the case?

In fact, the pressure problem started right after the installation. At the beginning, we have to top up the pressure like every week. After a few weeks, the problem disappeared, it's working beautifully for 3 months or so until a month or so ago, it needed topping up everyday!

Please, I badly need some advice here; I am afraid neither my plumber nor the valiant engineer are able to solve this mystery eventhough the boiler is newly stalled and is under manufacturer guarantee.

Dot :mad:
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Did you ensure the boiler was stone cold at the start of your pressure test and was not operated for the 20 hours?
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I found the leak! At long last, it is in one of the newly installed pipe for my new radiators. I only found out when we pulled the tumble dryer out and saw a big puddle of water. The leak explains the big drop of boiler pressure.

Is it common that new pipes leak? Or is it an indication of bad workmanship? I am now worried that a new leak will develop somewhere else after this leak is fixed. Can anyone give me some advice what I can do to avoid me going through the same nightmare again? I have been invesgating this leak for a few months!

If it was the actual pipe leaking I would think it's faulty materials, If however it's a joint that failed it would be down to poor workmanship but any plumber worth his salt would have found this quite easily.

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