I tried removing the AAV when I rebuild the standpipe and water was still backing up. Are you saying that whether the vent is 12” or 12’ above the standpipe it wouldn’t make a difference? Thanks again for your help.Not sure if you mean extend the vent up to the attic WITH OR WITHOUT the AAV.
I'd suggest you try it with the AAV removed, without extending the pipe, to test/confirm your suspicions.
The trouble with AAV's they can remain closed if they don't sense a negative pressure. And a high volume from a washing machine could cause that , particularly if that 2" line is not dumping into a 3" line.
You may see water backing up that open vent line if that was the case.
The arrangement you see in that picture is no longer. I have corrected as everyone has suggested in previous posts-- it is done properly.Assuming the arrangement was as I see it, where the vent height is shown lower than the standpipe, I assume it was coming out of the vent pipe. Which means it was not due to the lack of air. It means it's not flowing due to restrictions in the drain line.(Partial blockage or pipe too small.)
Have you tried snaking the drain line for possible partial blockage?
Can you determine if that 2" line connects to a 3" nearby? (Too bad they do indicate how close the 3" pipe should be.)
Options to improve, if not partially blocked.(After snaking)
Raise stand to 42" above trap weir.
Raise AAV to 6" above the top of the standpipe.
Or add a laundry sink and dump washer into that.
"Standpipes shall be individually trapped. Standpipes shall extend not less than 18 inches (457 mm) but not greater than 42 inches (1066 mm) above the trap weir. Access shall be provided to standpipes and drains for rodding."
Yes, I jackhammered out the floor, removed the trap, and connected directly. It is not double trapped.Just saw you previous posts on this subject. From April I believe.
So I must ask, since you didn't do what frodo had suggested. i.e. install stand pipe directly into old shower trap. Or maybe you didn't fully understand what he was suggesting.
Did you remove the shower trap or is it now double trapped. Which of course is a no-no.
The 2" shower drain it itself may have caused a problem. That we can't say at this point but I think 2 traps have a worse potential effect.
Water was not coming out of the vent line when I removed the AVV... and no, I corrected the AVV placement, it is now 12" above the standpipe.So then my question should have been, was the water coming out of the vent line when you removed the AAV, and was it still lower than the top of the standpipe?
Either way, it still a sign of a restriction.
The reason I suggested to raise the standpipe to it's maximum allowed height was to reduce the water flow. In other words the high the washing machine pump has to lift the water the lower the flow rate should be.
Did you ever look to see if you washer is one of those that have a much higher discharge rate?
oops! sorry I missed your answer on the traps until I refreshed the screen.
I really screwed up on that first one, just threw it together without doing any research.This is probably not critical, but your Studor vent looks undersized.
It looks like you have a reducing fitting on the 2” pipe, then the small AAV fits inside that reduced fitting.
So you are no way getting a 2” cross section of venting air.
I don’t know any code requirements, but common sense tells me it is too choked for vent air.
So if anything, I would suggest an increaser fitting, then a bigger AAV.
Not that this is causing your backup now, but it should help for long term.
LG WT7100CW... I’ll call them today. Thanks.It won't allow more air in than when you had the AAV completely removed. I think Jeff probably missed that.
It also won't let more air in if you raise it. In fact, theoretically, by making the vent pipe longer would only decrease the amount of air. Although insignificantly.(friction loss.)
You may also want to look at the owners manualto see what it says for maximum height you can raise the hose above the machine. That would give use an idea as to how much pressure it's capable of, safely.
Because the next step MAY be restricting the flow a little more by other means.
What's the name and model no.? I may try to check on that through the manufacturer.