Opposite of an AAV?

[epsilonGreedy]

Is it possible to buy a 110mm valve that operates as an air expulsion valve?

 

I ask because looking at the mechanism of the the AAV I purchased on friday it appears the close under negative drain pressure.

[PeterW]

Nope - May look that way but the diaphragm moves down to allow air into the pipe. 

[ProDave]

If you had one that opened on positive pressure it would let all the stink into the house and might as well not be there.

[epsilonGreedy]

With the disk in the raised position there is an open route for air and when lowered is seems closed.

 

It came out of a Bret Martin box but nothing on the component indicates a part number or manufacturer.

[PeterW]

If it’s a BM one then there will be a part number cast into it somewhere 

[epsilonGreedy]

5 minutes ago, ProDave said:

If you had one that opened on positive pressure it would let all the stink into the house and might as well not be there.

 

Ok. Just thought it was possible that venting off positive drain pipe pressure was required at times hence the part I am looking at.

 

In my case I need an AAV for the start of the under static caravan foul drainage plan and the more I look at this component the more convinced I am that it works in reverse.

 

I will leave the mini stack open for the moment, buy a genuine Brett Martin AAV and then compare.

[Gone West]

A Brett Martin AAV.

 

[ProDave]

Just connect a vent stack to the static caravan, that is what I did.

[epsilonGreedy]

5 minutes ago, PeterW said:

If it’s a BM one then there will be a part number cast into it somewhere 

 

 

I have looked in daylight, nothing to be seen.

 

Will keep you posted on developments.

[epsilonGreedy]

@PeterStarck yes mine looks the same but in black. Can you see a part number? My box says BS487.

[epsilonGreedy]

5 minutes ago, ProDave said:

Just connect a vent stack to the static caravan, that is what I did.

 

 

I did not want a roof height stack because I did not want the associated the hassle and screw holes of supporting the stack hence the plan for a short external stack at about toilet seat height.

[Nickfromwales]

16 minutes ago, epsilonGreedy said:

 

I did not want a roof height stack because I did not want the associated the hassle and screw holes of supporting the stack hence the plan for a short external stack at about toilet seat height.

If the pipe falls less than 1300mm invert to invert you dont really need one tbh.

[Gone West]

6 hours ago, epsilonGreedy said:

@PeterStarck yes mine looks the same but in black. Can you see a part number? My box says BS487.

Yes that's what it's says on their website.

 

http://www.brettmartin.com/en-gb/plumbing-and-drainage/products/plumbing/push-fit-soil.aspx