Bad smell from boiler condensation tube when running hot water

[xalvo12]

We have noticed a bad smell when running hot water and think it might be linked to the boiler condensation pipe (the water itself doesn't smell)

We noticed that the top of the condensation pipe isn't sealed properly but I have also been told that this is normal (picture attached)

So far I have cleaned out the trap and re filled it a few days ago, but no change, any advice?

 

[Matt1]

We have noticed a bad smell when running hot water and think it might be linked to the boiler condensation pipe (the water itself doesn't smell)

We noticed that the top of the condensation pipe isn't sealed properly but I have also been told that this is normal (picture attached)

So far I have cleaned out the trap and re filled it a few days ago, but no change, any advice?

I presume the smell is coming from the sink when you run any tap. The hoses in the machines can drift up. The water running away can pull the trap away and let the drain smell up. The upstand trap that the condensation pipe is attached too could dry up and let the drain smell up. Its usually the dirt in the pipe and plug waste that smell.

 

[DuncanM]

Should be sealed. Would not take much a glued reducer with a compression.

 

[Matt1]

Should be sealed. Would not take much a glued reducer with a compression.

It’s actually done right, the gap and trap. Boiler manufacturers require the air gap for back fill. If the drain backs up the boiler will flood internal.