Open drain under boiler

[SunnyUpNorth]

Our boiler is in our cellar. It has an open drain underneath it. We had our cellar converted last year and the boiler boxed off in a little room. We have been plagued by awful sewer smells for the last few months. There were a few red herrings along the way that masked the smell and also made us think it was coming from other areas of the cellar but I now think it’s coming up through this open drain.

I’m wondering if the boiler pipes can be extended down into the drain a bit and some sort of cap/seal put over the drain to stop smells coming up. I asked a local plumber who did the service recently but he hasn’t come back to me, so would be interested to hear if anyone has had this done.

A proper cover for indoor manholes and probably another drain inflow with a water trap for the pipes to flow in. If it’s a sewer get an anti blow back thing fitted as well. Sewage in the house isn’t fun

Great thanks, you sound like you know what you’re talking about. So just to double check - are you saying to treat them as two different things? So fit a new pipe for the boiler pipes to go into, possibly with a u-bend and then separately cover up the hole with an internal man hole cover? I’ve just looked at those and they don’t have holes in them so obviously the existing pipes can’t feed through that.

The builders at the time apparently carried out some kind of test to check that water/sewage would back flow through the pipe but in retrospect I’m not sure how thorough that test would have been given they did a runner on us!

Would the above be carried out by a normal plumber or a heating engineer? Thanks so much for your help.

Start by getting a plumber to test the drain. It might or might not connect to a sewer. It might or might not be cracked and leaking.

A drain in a cellar floor has to run downhill (first rule of plumbing) so a sewer would need to be unusually deep.

When the house was built there was probably a manhole nearby. It might have been hidden or concreted over by now.

It probably ought to have a yard gulley with trap on it.

Thanks pigletjohn. I think it probably does run into the sewer pipe and it is quite deep as we are on a bit of a hill so has to be deep enough to run under our sloping driveway at the front.

I’ve already had a camera down the pipes twice, and a power flush which wasn’t really required but they did it as they were there anyway. The camera showed the drains to be in good condition but we didn’t look at that small section from the boiler drain specifically.

Would I get a normal plumber or a heating engineer? As it involves the boiler pipes I was thinking heating engineer but the rest of the job feels more like a normal plumber job.

Plumber or drain man.

Not a "gas" job.