Coltri MCH6 compression fitting on tower

[lukejjon]

Hi,
I have a Coltri MCH6 and I've removed couple of the compression fittings that screw into the filter tower and also a couple from the condensate tube as they were quite dirty and little rusty. My question is when I re-install them what do I put on the threads that screw into the tower to seal it?
Thanks

 

[Snusmumrik]

Hi,
I have a Coltri MCH6 and I've removed couple of the compression fittings that screw into the filter tower and also a couple from the condensate tube as they were quite dirty and little rusty. My question is when I re-install them what do I put on the threads that screw into the tower to seal it?
Thanks

PTFE tape.

 

[lukejjon]

ok, thanks I'll give that a try

 

[Wookie]

PTFE tape.

Aahhhhhh!!!!!!

I have never met a tower fitting on any type of tower (aside from the relief valve in the moisture separator) that isn’t o-ring boss.

Compression fittings NEVER get teflon tape. So is it where the fitting goes in the tower, or where the tubing attaches to the fitting?

 

[Agro]

I have never met a tower fitting on any type of tower (aside from the relief valve in the moisture separator) that isn’t o-ring boss.

Except on a Coltri MCH6 (today it has an other name). They have conical threads in the filter tower. Originaly they use no sealing at all, they just screw the fitting (conical external thread) into the filter tower (conical internal thread). The fitting's steel seals on the filter housing's aluminium.

If you unscrew the fitting it will probably not seal again this way. Best solution is teflon tape, this works perfectly. I tried Loctite which did not seal for a long time. And Loctite smells, I don't want to have this in my breathing air.

Use Teflon and everything is perfect.

 

[rob.mwpropane]

@Wookie I've only known them as BSPP (British Parallel Pipe) fittings. Is that correct?

@lukejjon if that's correct, then they don't get teflon but they do get a sealing gasket like this; This is what my filter housing takes.

USIT Sealing Gasket R 1/4 - August Industries LLC

This is a bonded sealing gasket used to seal 1/4 BSPP male thread fittings designed for shoulder sealing. Used with ADP-0021 and ADP-0021SS

www.augustindustries.com

 

[Wookie]

@Wookie I've only known them as BSPP (British Parallel Pipe) fittings. Is that correct?

@lukejjon if that's correct, then they don't get teflon but they do get a sealing gasket like this; This is what my filter housing takes.

USIT Sealing Gasket R 1/4 - August Industries LLC

This is a bonded sealing gasket used to seal 1/4 BSPP male thread fittings designed for shoulder sealing. Used with ADP-0021 and ADP-0021SS

www.augustindustries.com

Rob, I’ve only known BSPP on Mako and Bauer, and ORB on Coltri, but @Agro says it’s BSTP or NPT. I’ve never seen tapered threads on a 6000 PSI air fitting, but I haven’t seen everything yet.

 

[Dave1w]

Rob, I’ve only known BSPP on Mako and Bauer, and ORB on Coltri, but @Agro says it’s BSTP or NPT. I’ve never seen tapered threads on a 6000 PSI air fitting, but I haven’t seen everything yet.

It's Coltri..... 1/8npt I believe. That's what they do.

 

[Agro]

It's a BSPT 1/8 thread. Not a NPT.

 

[happy-diver]

And when you've seen some of the aluminium filter tower corrosion, like rabbits digging out the thread
around steel fittings on Bauer towers using USIT it might be a good idea to wrap some tape around too