I work on a council contract fitting bathrooms, kitchens and heating systems in West London.
The discharge hose for the washing machines must be put onto a spigot trap under the sink (no standpipes allowed).
I was called back to a recent property we have done to investigate a problem with the W/M waste coming up into the sink, this is quite common in the area and is due to the stacks or underground pipes being blocked due to years of abuse. This property was different though.
The sink water drained very fast, sucked the seal out of the trap and proceeded to gurgle on and on and on.....I shone a torch down the waste and could see about 5mm of water in bottom of trap.
The outlet from the trap immediately went vertical to the floor where it converted to 3" dia under the kitchen floor thus explaining the trap seal being broken. The tenant then ran the washing machine and as soon as the waste was discharged it filled the sink up, eventually draining away and sucking the seal out again.
I returned to the property and fitted an In-line Anti Syphonic Trap.....No success. Returned again and fitted an Air Admittance valve.....this stopped the seal being sucked out when sink waste released but the W/M waste still filled the sink up.
I'm baffled, at first I assumed it was air in the trap stopping the W/M waste going down...now I don't know.
Any ideas?
Sorry for the long boring post but wanted to give as much info as poss, any help will be much appreciated.
The discharge hose for the washing machines must be put onto a spigot trap under the sink (no standpipes allowed).
I was called back to a recent property we have done to investigate a problem with the W/M waste coming up into the sink, this is quite common in the area and is due to the stacks or underground pipes being blocked due to years of abuse. This property was different though.
The sink water drained very fast, sucked the seal out of the trap and proceeded to gurgle on and on and on.....I shone a torch down the waste and could see about 5mm of water in bottom of trap.
The outlet from the trap immediately went vertical to the floor where it converted to 3" dia under the kitchen floor thus explaining the trap seal being broken. The tenant then ran the washing machine and as soon as the waste was discharged it filled the sink up, eventually draining away and sucking the seal out again.
I returned to the property and fitted an In-line Anti Syphonic Trap.....No success. Returned again and fitted an Air Admittance valve.....this stopped the seal being sucked out when sink waste released but the W/M waste still filled the sink up.
I'm baffled, at first I assumed it was air in the trap stopping the W/M waste going down...now I don't know.
Any ideas?
Sorry for the long boring post but wanted to give as much info as poss, any help will be much appreciated.