First time I've ever used a micron guage. 410a split system. I pulled vacuum and here are my results:
Pump shut off at 144 microns.
+1 hour: 275 microns (131 increase).
+1 hour: 339 microns (62 increase).
+1-3/4hour:413 microns (76 increase).
So in 3-3/4 hours 269 micron increase.
Is this amount of creep normal? Should this creep have stopped at some point?
Also, I was thinking of leaving the vacuum pump on overnight but it's getting cold at night (34F low). What is too cold for leaving a pump on?
Thanks and have a great day!
Originally Posted by nlovas
Sounds like a good vacuum and I applaud you for doing it right!!!
Outside pressure differences, improper hoses and/or connections could be the reason for this creep. Internally you have a dry and clean system. Charge that sucker up.
At 144 on your initial pull.....you're good....
A small creep is fine....
If you would have gone from, say, 144 to 500 in a matter of a few minutes,
I would say you have a problem.....
For a residential, split system, it shouldn't be necessary to leave a pump
running over night...
With the proper tools and set ups, a solid, 200 micron (or lower) vacuum
can be pulled in 20 minutes....
Great job using the micron gauge....glad to see more guys taking pride in
I need a new signature.....
Thank you. You've given me important information I need to help me do a good job.