Pipe dope and sealant

Information on some common auto air conditioning topics.
Archived Forum

Moderators: bohica2xo, JohnHere, Tim

Post Reply
Posts: 5
Read the full article
Joined: Wed Jul 14, 2021 2:47 pm

Pipe dope and sealant

Post by JCTyler »

I'd like to know what kind of pipe sealant is used on auto a/c fittings that are NPT and NPS? Would pipe dope be used?
User avatar
Posts: 955
Joined: Sun May 13, 2018 10:20 am
Location: South Carolina Upstate - USA

Re: Pipe dope and sealant

Post by JohnHere »

I wouldn't use any kind of plumbing pipe dope for NPT or NPS fittings because of the risk of contaminating the system with incompatible substances.

I wouldn't use plastic tape on the threads, either, because any remnants of the tape that inadvertently find their way into the system could clog critical components.

Nylog Blue is the only sealant I know of that will do the job and that is compatible with MVAC systems.
Member – MACS (Mobile Air Climate Systems Association)

Thankful for the responses you have received? Please consider making a monetary donation to the Forum.
Post Reply