Vacuum question

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#1

I just setup my infusion setup and used parts from Joes woodworkers to make a setup like that to basically kick on the pump and have stored vacuum just encase a leak is developed later.

I have a robinair 15500 pump that I just purchased and right now I have one of the analog gauges. I know everyone recommends a digital one but I just haven’t had time to pick one up and I’m still sourcing other supplies.

My question is how long does it take you to usually pull down to 29 or 30hg? Also I’ve been running my pump for the past 15 min but can only get down to 26.5.

I did a leakdown test for 10 min but the needle hasn’t moved. So I’m guessing these things may have factors?

  1. I’m located in Philadelphia so that’s about as level to sea as you can be.

  2. My gauge is slanted sideways and not straight up or even facing up. It’s on it’s side and facing outward.

  3. When I first opened the gauge it said to open the top to release the pressure. I did that and it went from being 5 to 0 so I believe I did that correctly.

  4. I have a small leak somewhere that I don’t notice yet.

  5. The robinair 15500 isn’t good enough?

Any advice is welcome. Thank you.

Edit: After an hour of running I was able to get 27.5

#2

Well I put silicon around all the joints and it eventually pulled down to a 28hg reading…

My pump can pull 35 microns so I’m thinking it should be closer to 29 even with my gauge.

I’m going to put some clamps on the hoses tomorrow from the auto store and if that doesn’t work I’m going to have to disassemble all the brass fittings/clean everything up/and probably use not white but pink sealant tape or something.

I did shut the pump off after it was on 28 for a while and left it be. I checked the gauge again and 2 hours later it dropped to 27 so I know I have a small leak somewhere.

I’m also not hooking it up to a bag at this point. It’s just shut off with a ball valve so I’m not sure if that makes a difference or not. Tomorrow I’ll try plugging the hole first just encase there’s a slight leak there.

#3

Did you put oil in the pump?