How often should a combi need topping up ?

[Jonny brown]

A friend of mine has to top his combi up every 3 months or so . He called British gas ( he has cover ) the engineer said it all looks good and sometimes older boilers lose water , it's only 6 years old ! .
Is the engineer talking BS ?

 

[muggles]

Yes. Shouldn't need topping up unless there's a fault

 

[Daviesmith]

Fernox f4 express . It worked for me last year

 

[Madrab]

I guess the question is how often do they need to top it up?

I have to disagree about leak sealer though, IMO by it's very nature it is something that shouldn't need to live in a central heating system with all it's moving parts/seals and micro waterways, even when it's suggested that it doesn't cause issues.

I would recommend finding the leak and fixing it.

 

[ianmcd]

+1 for not using leak sealer, it causes more problems than it sorts

 

[Jason Mahoney]

You may have dealt with this already but if not, firstly, don’t put any leak sealer in it. Secondly, did you say topping up every 3 months or so ?
Couple of things to consider, when topping up, under what circumstances is this being done, what is the pressure dropping to before being topped up what is it being topped up to? Is the system cold when being topped up (very important that one).
In a perfect world, we would set set pressure when system cold to around 1.2 - 1.5 bar (depending on boiler), when pressure drops to below 0.7 - 0.8 bar, would top it up again, this depending on size of system could be around very 3 to 4 months. Sealed systems naturally lose pressure over time through air/hydrogen being produce, then venting through auto air vent, water evaporates as well. Chances are this is normal operation.

hope that is of some use

BG engineer