Auto Bypass Valve on 15mm Pipework

[DIYWell]

Time to fit an auto bypass valve to my heating system but there's absolutely no space to fit a 22mm one.

My plan is to pop one into the flow/return of the 15mm pipes that the rads feed from and use a 22mm ABV with compression reducers to fit the 15mm pipes.

Is there anything I should look out for?

 

[stem]

How about a 15mm Auto Bypass valve?

 

[DIYWell]

They're like hen's teeth and ridiculously expensive. Danfoss do 15mm, 22mm and 28mm versions but the bodies are identical; they just change the connectors.

 

[stem]

I've got an AVDO15 as per the link above I posted, it simply replaced the original 15mm manual gate valve that was just cracked open. Mine does appear to 'let by' quite a lot though even when the heating demand is high.

 

[Madrab]

Just get a 22mm valve and pop a couple of 22>15mm reducing sets in them

 

[Mottie]

I've got an AVDO15 as per the link above I posted, it simply replaced the original 15mm manual gate valve that was just cracked open. Mine does appear to 'let by' quite a lot though even when the heating demand is high.

Is it adjusted correctly - sounds like it isn’t. Had a similar problem with mine until I adjusted it. Very easy. Plenty of 'how to's' on the net.

 

[DIYWell]

Just get a 22mm valve and pop a couple of 22>15mm reducing sets in them

Yep, I've got a stack of those. Way easier to use than the single piece reducers.

 

[Madrab]

single piece reducers.

Absolutely hate snap reducers, with a passion, inventor should have been lit up IMO

 

[DIYWell]

Absolutely hate snap reducers, with a passion, inventor should have been lit up IMO

Nah, they should have been forced to use then in a tight space and see how they liked skinned knuckles