Just have a general question about ac vacuum pumps. I tried to use one the other day for the first time, and couldn’t figure out how to get the pump itself to hold pressure.
First I got a junky parts store rental pump and followed instructions to check oil.
Block off suction port, let run and check oil level
Slowly add oil as necessary
As soon as I turned it on, freon started blowing out of the oil pour cap, so i tightened it down and tried again. Same result. So I figure it’s just a shot pump and bring it back. They swap it out for a new in box unit and I bring it back and the same exact thing happens (but with just air this time.) Am I just having bad luck or is this normal?
Didn’t even make it to that point. I was just test running the pumps per instructions and number one blew freon from the oil cap and number two blew air since it was new and unused prior.
When you write: “I tried to use one the other day for the first time, and couldn’t figure out how to get the pump itself to hold pressure”, what exactly did you do other than “tried to use one the other day” that resulted in the pump not holding pressure?
" * First I got a junky parts store rental pump and followed instructions to check oil.
Block off suction port, let run and check oil level
Slowly add oil as necessary
As soon as I turned it on, freon started blowing out of the oil pour cap, so i tightened it down and tried again. Same result. So I figure it’s just a shot pump and bring it back. They swap it out for a new in box unit and I bring it back and the same exact thing happens (but with just air this time.) Am I just having bad luck or is this normal?"
I’m pretty sure you don’t understand me. The instructions say to test run the unit (without being hooked up) to circulate and check oil levels. So they weren’t even hooked up to a vehicle or cooling system. Simply plugged into an outlet.
Did you hook it up to your AC system when “freon started blowing out of the oil pour cap”? If not, where did the freon come from that blew out of the oil pour cap?
There is no refrigerant in a vacuum pump, if the pump was stored upside-down you might see a mist of oil discharged from the exhaust vent but that doesn’t indicate failure.