Can't pull vacuum in my mini split install .

[Black Oak]

I was dejected as I tried to pull a vacuum , and was clueless as to what the problem was . I was confident I didn't damage the line set , and my flares and connections were fine . Turns out it was the seals on the vacuum hoses , which were bad . A more experienced person would have probably known to check , but I learned the hard way . Up and running , all's well now .

 

[kbeefy]

well OK then.

 

[ripperd]

For some car AC work I rented the vacuum pump and guage set from Oriely Auto. The first set I rented was all beat up and the seals all torn. Couldn't pull full vacuum nor would it hold it. 2nd pair I rented were mint and worked great. Definitely something to watch for. The rentals are free after you return them so I couldn't complain too much, even though it required an extra trip.

 

[metlmunchr]

The gaskets get ruined by over tightening the connections. Car parts stores with loaner tools should check or replace them regularly as the natural tendency for people not used to using gauges is to overtighten or even help the knurled nuts with pliers.

 

[LS6 Tommy]

I was dejected as I tried to pull a vacuum , and was clueless as to what the problem was . I was confident I didn't damage the line set , and my flares and connections were fine . Turns out it was the seals on the vacuum hoses , which were bad . A more experienced person would have probably known to check , but I learned the hard way . Up and running , all's well now .

BTDT many years ago. Ever since then I replace hose seals annually and more recently I started to only use the heavy duty "black" vacuum rated hoses for my manifold. Using true vacuum rated core removal tools really helps with evacuation, too.

Tommy

 

[PoorUB]

When I was in the trade doing service work I would replace those pesky seals every time I pulled a vacuum, maybe a few times a week. It was faster to swap out the seals than to wonder why I couldn't pull a vacuum.

 

[65ranchero]

BTDT many years ago. Ever since then I replace hose seals annually and more recently I started to only use the heavy duty "black" vacuum rated hoses for my manifold. Using true vacuum rated core removal tools really helps with evacuation, too.

Tommy

And in a pinch when you run out of seals I have used sections of vacuum hose cut to the right length. the only problem is they don't last long.