Baxi Duo Tec Combi Boiler Fault

14 Feb 2009
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United Kingdom
I had a new Baxi Duo Tec Combi Boiler fitted in September 2008, it works fine but needs frequent top up's of water, is this normal or should I call a plumber, the company that fitted it has disappeared!
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what are ya topping the pressure up to? should fill to around 1 - 1.5,
if thats what you have been doing chances are you have a slight leak somewhere.
Top up boiler pressure then isolate boiler from system.

If pressure remains constant, leave for as long as possible, then drops when you open the ch isolating valves you have a leak on the system.

If it drops whilst isolated you have a boiler problem.
Thanks for the reply, I've been topping it up to about 2, and it needs filling every week, I have noticed that there is a lot of condensation coming out of the flue on the outside of the house which causes a small puddle of water to form beneath it on the ground, the boiler and flue is situated on the first floor and the old boiler did not do this, any ideas?
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Sounds like they have installed the flue incorrectly, but is not related to your pressure problems.

If the pressure is going down you have a leak.

Make sure your little puddle is not actually coming from the pressure relief valve rather than the flue.
how many rads are on the sytem and is there a lot of pipework.if your putting the pressure at 2 bar cold , it could be overpressurizing when hot.

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