baxi 133 he plus losing water

[baileyb]

Hi new to this i have a baxi combi 133 he plus 4 years old but in the last 3 months it has started to lose water i have checked all visable pipes and connectors but cant see any leak anyone one any ideas

 

[Puddle]

How much pressure drop are you getting over what time period,how many rads/how big is system,is all ground floor pipework visible ?

 

[baileyb]

i am filling it to about 1.25 to 1.5 bar bar and lose the water over about 2 to 3 weeks has only just started i have 12 rads but it has only started since the heating has been off dont know if this makes a difference about half the downstairs pipe work is visable as this is new the rest is microbore in the walls but know where most pipes are and the walls seem fine there

 

[Puddle]

Presume you are not letting pressure drop right down before you refill,this is a very small leak indeed,double check all rad valves as offending valve maybe just damp to touch,it could be inside the boiler,small leak on heat exchanger and evaporating during use,should be checked for any signs of leakage
Maybe get a gas plumber in to check this and maybe isolate the boiler from system and run in hot water mode only for a while during the nice weather as see if still falls,at least then you will know if boiler or system
You could add a leak sealer however best to find leak if possible

imho

 

[baileyb]

no the boiler cuts off at about 0.75 bar not much of a leak just always seems to stop working when im trying to get a shower i will check all the valves again and if i cant see anything i will get a plumber or one of those boiler cover plans thanks for all your help