The final connections to the heat pump best jointing method.

[MikeSharp01]

I am about to make the final water connections to the heat pump (HP). I want to use a 28mm barrel to the HP connecting to a flat face valve them a swept 28mm bend then onto the flexi to the flow / return pipes running alongside the HP. I was wondering what method to use the joint the barrel into the HP. Liquid PTFE, straight PTFE tape or a more old school method. I prefer the liquid PTFE but am happy to take advice from experts. 

[SimonD]

None, you should just have a nice little rubber (epdm) washer in there on the flat face.

[MikeSharp01]

1 hour ago, SimonD said:

None, you should just have a nice little rubber (epdm) washer in there on the flat face.

That makes sense going onto the fkt face valve o it's the same for the female set into the machine is it - neat.

[MikeSharp01]

Just tried it and the washer is floating when the barrel is tight and it does not look like it has a flat face at the bottom of the socket just a small lip! 

[SimonD]

20 minutes ago, MikeSharp01 said:

Just tried it and the washer is floating when the barrel is tight and it does not look like it has a flat face at the bottom of the socket just a small lip! 

 Can you share a photo?

 

[MikeSharp01]

Yep here are a few. The total depth of the thread in the socket to the lip is 16.87mm the thread length of the barrel plus the washer is 15.76. Also on the return there is no lip more a radius to the pipe diameter inside.

 

[SimonD]

2 hours ago, MikeSharp01 said:

Yep here are a few. The total depth of the thread in the socket to the lip is 16.87mm the thread length of the barrel plus the washer is 15.76. Also on the return there is no lip more a radius to the pipe diameter inside.

 

 

Oh, I see! There was me being a bit dopey. A thread sealing compound will do it - I always use Loctite 55 myself - your PTFE liquid should do the job.

[MikeSharp01]

Thanks @SimonD I will get some loctite 55 - try and copy the pro's eh.