The waste run in my new kitchen is very long, and hence the BCO insisted on installing an AAV on the 40mm pipe. The plan is to fit it under the worktop next to the kitchen sink.
My logic suggests that the AAV needs to be fitted above the highest possible water level in the sink. IS this really the case? i.e. do I need to re-think my plan?
PS: I seem to recall seeing this done is my proposed way before, but cannot remember the details.
I don't think that's the case for a 40mm waste run. They are commonly integral with the U-trap, which will always be lower than the sink.
That's what you're supposed to do when fitting an AAV to a soil pipe. If you need to get access to the pipe for rodding by removing the AAV then any water trapped in the sink will not flow out through the AAV since it's at a lower level. Having it lower than the highest water level doesn't stop it working but may be messy in case of a blockage.
You can always drain the sink by undoing the U-bend.
MBQ
On Wed, 8 Feb 2006 00:14:19 -0000, a particular chimpanzee named "JoeJoe" randomly hit the keyboard and produced:
Are you sure he's not talking about an anti-vac trap [1] which is fitted instead of the standard trap?
[1] I'm sure Dr Dibble will be along in a short while to extol the virtues of HepVO traps.HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.