DIY Doctor UK DIY Forums

Hello there

The flue of my new gas condensing combi boiler makes noises in therain; it sounds like rain is getting in. At the same time, I noticed today that water was gurgling up through the sink plug hole (I'm assuming the two things were related - it may simply have been that the drains were being overwhelmed by the heavy rain, although I've never noticed this happening before).

The flue pipe slopes upwards from the boiler to the exterior wall - is this to allow the gases to escape? I'm worried that it's letting rain in, and because the system is new and I've never had central heating before, I'm a bit twitchy about safety (the noises are really quite loud!)

Is anyone able to offer me any comfort, please? I realise I'm almost certainly just being daft...

Well your boiler is DROWNING. Either water is getting into the end of the flue (dripping gutter above, high wind/weather area or leaking pipe above) or your condense is not draining away. Common problem is incorrect connection of the condense discharge pipe to soak away drain off point, e.g. gutter down pipe, and the water backing up in the gutter pipe and then water backing up into boiler, either from condense failing to drain away or rain water getting in.