Filling loop double check valve - which side?

[AWheating]

if you dont fit the check valve on the mains side and you inject/fill your chemicals via the filling loop then you could risk contamination of the supply.

after all you fit a check valve at an outside tap not at the end of your hose pipe

 

[mountainman]

Thanks - that wasn't my intention though!

I was speaking to a plumber at the shop I purchased the filling loop from. I wasn't going to use PTFE tape at all, just jointing compound. Instead of using jointing compound, he advised me to wrap 6/7 turns of PTFE tape around and on the compression olive.

The original valve did not have any PTFE tape on the compression.

Now I know this is a wind up lol.

Lead me to the darkened room and the fridge full of beer!!!

 

[SafeGasInstall]

i am with jcplumb

 

[SimonJohns]

i am with jcplumb

Ditto

 

[PlumbBobBob]

Ditto

me too

 

[M.Joshi]

Edit: Oops, replied in wrong post!