Soil Air Admittance Valve Position

[SMG]

My downstairs loo has an air admittance valve which does not reach the height of the water cistern. Its impossible to raise the height where its located. Could I remove & blank the existing vent, then use a 40mm strap on boss with a smaller air admittance valve?

Like This.

http://www.level.org.nz/fileadmin/downloads/Water_Use/LevelWaterFig48.pdf

 

[Agile]

Why do you want to increase the height?

Tony

 

[SMG]

Because the soil vent is lower than the pan, & there is no room for the extra height. I can fit a boss with a 40mm waste pipe, terminating high enough for the water not to flow over, I`m wondering if a 40mm air admittance valve will allow enough air into the soil so the toilet wont gurgle.