Failed STP pump and stinky loft

[Thorfun]

need some help. our compressor pump on our one2clean failed a couple of weeks ago and it's taken this long for them to send a replacement pump (next time I'll just buy my own as a spare rather than wait for a warranty replacement!) so the STP hasn't been aerated for quite a while. I fitted the new pump yesterday and things are moving again in the STP but there's an awful smell in the house. our loft space is split in to two halves, we have a soil vent pipe above the master bedroom on one side of the house and then on the other side above the kids rooms each stack for their bathrooms has an AAV. it smells really bad in the loft above the kids' bedrooms.

 

I'm wondering if there's been some kind of pressure build up and the AAVs have failed? is that a thing?

 

obviously it's late on a Sunday so nothing is open to get replacements. if I can find a blanking cap for the soil pipes to block them off in the loft and remove the AAVs until I can buy new ones is that a bad thing? or do I just need to live with the stink until I can get to Screwfix tomorrow to replace the AAVs?

 

any other ideas to help? if I lift the lid on a couple of the manholes leading to the STP then there's a bit of a whiff as well. I'm wondering if I need to get the tank de-sludged asap as maybe no aeration for a couple of weeks has screwed up the cycles in the tank and anything new deposited in the last couple of weeks won't now break down.

 

I know there are lots of STP owners here so if anyone can give any advice then I'll gratefully listen!

 

tagging @Nickfromwales as he knows everything. 😉 

[ProDave]

How long since last de sludge?

 

Check none of the traps have run dry, just pour a bit of water down each to make sure.  An AAV won't let a smell in unless it has failed but that is unusual.  Try taping a plastic bag over the AAV's to see if that stops the smell?

[Thorfun]

1 minute ago, ProDave said:

How long since last de sludge?

 

Check none of the traps have run dry, just pour a bit of water down each to make sure.  An AAV won't let a smell in unless it has failed but that is unusual.  Try taping a plastic bag over the AAV's to see if that stops the smell?

STP has never been de-sludged yet but it's only been in use just over a year really. I'll check the traps but we use every sink/shower/toilet/basin regularly. the only anomaly is in the master en-suite we have 3 x dry-traps as space-savers.

 

good idea about the bag of the AAVs and I'll give it a go but I'm now actually wondering if the smell somehow got in to the loft and as it's airtight has nowhere to go so is just lingering! no idea how it would've got in there though if one of the AAVs hasn't failed though.

[Thorfun]

4 minutes ago, ProDave said:

An AAV won't let a smell in unless it has failed but that is unusual.

is there a way to test an AAV? or, for the £60 it'll cost to replace them, shall I just replace them anyway?

[ProDave]

If the AAV has failed and is letting air out, then it will inflate the plastic bad you are about to tape over it.

[Thorfun]

24 minutes ago, ProDave said:

If the AAV has failed and is letting air out, then it will inflate the plastic bad you are about to tape over it.

ok. neither bag that I elastic banded to each AAV inflated so I think they're ok.

 

think I found the source of the smell coming in though. we have a header tank in the loft for our RWH to flush the toilets with (we don't use it anymore as it was making the cisterns brown and scummy and we had a pressure issue at one of the toilets) and the header tank has an overflow that goes in to the soil pipe just below the AAV. I didn't put a trap between the overflow and the soil pipe so smells can easily come back up and in to the loft that way. so I've stuffed a plastic bag in there for now and will see if that makes it smell less. I really want to decommission the header tank and just use the RWH for the garden but it's so ingrained in the toilet plumbing system that removing it is a real faff! I think I'll just drain the header tank fully and plug up the overflow for now.

 

it does still smell in the master bedroom though so maybe the dry-traps in there aren't doing their job properly.

 

I guess I need to fix the source and stop the STP from being smelly. I'm hoping that leaving it for a few days for things to start working properly again will help. otherwise I guess I'll just get it de-sludged and start again.

[Mr Punter]

3 hours ago, Thorfun said:

I really want to decommission the header tank and just use the RWH for the garden but it's so ingrained in the toilet plumbing system that removing it is a real faff! I think I'll just drain the header tank fully and plug up the overflow for now.

 

Well hopefully this will serve as evidence to dissuade others who are considering RWH in their home.  A water butt is probably the extent of what is useful.

[Thorfun]

19 minutes ago, Mr Punter said:

 

Well hopefully this will serve as evidence to dissuade others who are considering RWH in their home.  A water butt is probably the extent of what is useful.

Agreed. But it did help with the water calculations. 🤣

[crooksey]

Graf one2clean works with the control module controlling the blower and the pump, if an error code comes about it can throw the cycle off and you will have had no aeration.

 

Once its all running again, if it doesn't go away after 5 days, just get it emptied, it won't go away.

 

Always good to keep a spare pump and diaphragm rebuild kit for any sewage plant owners.