Easy question for those who know

[JohnD]

I want to fit a 22mm Spirovent into a 15mm pipe.

I think it would be handy to fit it with service valves above and below, in 22mm compression. But I have forgotten how to convert a 22mm fitting to 15mm. I have not needed to do it since before Crafty Steve was born.

there's some kind of brass adaptor cone, isn't there? What am I looking for, and are there some tips on best practice to avoid leaks?

I am anticipating that the service valves will be used approximately never, so I was thinking balls not gates. By using 22mm I will not constrict the flow more than necessary.

The device will be fitted into an existing vertical pipe that it fixed at the ceiling above and goes through the wall below, are there better ways than spring the pipe out to slip the fittings into place? It runs down a garage wall and I will fabricate an insulated cover for it, so appearance is not important. The pipes are wet so I don't want to solder them.

 

[chr15]

You can get reducing sets from the merchants made of brass and you put them in the fitting in place of the olive--or you could buy 22mm-15mm reducers in compression but they will take up more space and probably cost more.
Getting the fittings in place--if you cant spring the pipework then a soldered slip coupler would do the trick.

Just spotted that you cant solder because of water in pipe,not sure if you can get slip couplers in compression.

If you have a compression elbow at the top or bottom of the pipe run then you can assemble it by making that your last joint.

 

[hi-spec plumbing heating]

>Just spotted that you cant solder because of water in pipe

remove the water then.

 

[chr15]

>Just spotted that you cant solder because of water in pipe

remove the water then.

Very clever smart a*s but he says HE doesn't want to solder and even if he did sometimes you can't always remove all the water.

Read it properly next time.

 

[doitall]

The obvious answer is to buy an 1/2" spirovent

Anyways assuming you already have the AAv the you want a "Conex" 303, 3/4" x 15mm compression coupler.

If you have problems in that department get an Conex 303 3/4" x 22mm and a, conex 22 x 15 reducing set