You should have ventilation somewhere. Hopefully your soil stack has a vent at the top of your house. If so then the chamber vent is redundant, as it can vent through the inlet pipe.
Are these drain pipes old clay? Would you change them if you were me?
- Thread starter Matt723
- Start date
-
- Tags
- drain pipe pipe plumbing
- Joined
- 1 May 2018
- Messages
- 1,751
- Reaction score
- 527
- Country
I'm no expert here as I've only just discovered these exist. However, with a bung and a trap in the outlet to the chamber, isn't the vent necessary to stop the chamber becoming pressurized in any way and holding the flow back? Without chamber ventilation the flow in will be restricted by the speed/capacity through the trap?
i.e. a slug of water and other stuff from a toilet will be coming down the pipe and the air pushed ahead of it has to go somewhere. Without a vent it would be trying to blow through the interceptor trap.
The inlet pipe will vent the chamber. It will provide a straight-through route for air to enter or leave, as it does in every chamber without a Victorian ground level vent.
Provided of course that it does have a vent. Which it should, otherwise the toilet and/or basin wastes would frequently end up half-empty after flushing.
Provided of course that it does have a vent. Which it should, otherwise the toilet and/or basin wastes would frequently end up half-empty after flushing.
An air admittance valve is not sufficient, as this will only allow air to enter - not to leave.
Buchan Hell - when they block - need a power flushing machine - looks fine now though. Top pipe is an air inlet.
... google Hepsleve drain ...
Last edited by a moderator:
The Interceptor Traps were a Victorian idea to seal off the House Drains from the Main sewer in the road. They are a total PITA, prone to blocking, the stopper in the rodding eye often falls out, causing its own set of issues, and often, if they are giving frequent problems, the Interceptor is removed and a straight pipe fitted in place.
The Low level vents were designed as Air Admittance Valves, but invariably they stuck open, so people have blocked them off over the years. Its not required now, so cap it off if desired. The Victorian idea was, air passing over the top of the soil or vent stack would cause a negative pressure in the house drainage system, thus drawing fresh air in at the low level vent, through the system and out the top of the stack, thereby keeping the house drains aired, and avoiding the build up of 'drain air' which they initially believed was the cause of their ills.
Until they found out it was actually the water...
The Low level vents were designed as Air Admittance Valves, but invariably they stuck open, so people have blocked them off over the years. Its not required now, so cap it off if desired. The Victorian idea was, air passing over the top of the soil or vent stack would cause a negative pressure in the house drainage system, thus drawing fresh air in at the low level vent, through the system and out the top of the stack, thereby keeping the house drains aired, and avoiding the build up of 'drain air' which they initially believed was the cause of their ills.
Until they found out it was actually the water...
Thank you all, I learned a lot. Seems we hit the jackpot and got a crazy deep old clay pipe that would be a huge undertaking to replace along with a "+Buchan" hell"!
Drainage guys coming tomorrow for a map survey and CCTV hopefully all will be fine...
Also if one day there is an issue with this drain, I guess epoxy lining would be relevant here in order to avoid digging this deep?
Drainage guys coming tomorrow for a map survey and CCTV hopefully all will be fine...
Also if one day there is an issue with this drain, I guess epoxy lining would be relevant here in order to avoid digging this deep?
Assuming drain hasn't collapsed, then yes, patching or lining is a suitable method for repair. However, do not be talked into having this done if not needed!