bluvac question

[anthonyac1]

i hear often people say if you pull down to 500 microns you dont have a leak? even with a tiny seeper style leak. i have the bluvac and appion mega flow kit with out the manifold 1/2' comming off the pump to a T with 2 3/8" hoses to the appion crt. i could be wrong but im thinking maybe evacuating through your manifold that 500 micron rule of thumb might apply but with bigger hoses new oil and cores removed your pulling at a faster rate than the leak in turns your gonna continue to pull down the microns. i worked on a package unit dual circuit that had several leaks in the condenser coil i pulled both circuits down to 325 microns but once i valved off the core tools my microns started climbing pretty fast. the leak rate said 1.5 is there a leak rate that is acceptable? i know the bluvac is very sensitive but i wanna get maximum use out of any tool purchased im sure we all do

[ryan1088]

All depends on the size of the pump and how big whatever you're pulling on. If you used a 7 cfm pump on a window unit, I imagine you could get a pretty low number. Evacuating something that has had refrigerant in it can be tricky also using a micron gauge.

With that being said, I've only used my bluvac once....

[Brent Ridley]

Once you think you've pulled the system down to an acceptable micron level, valve off the pump and micron gauge from the system. Watch your bluvac gauge for 5-10 mins. After that time, check your micron gauge and that will be your final reading. This step is critical. The micron readings will rise a slight bit during this period but as long as they're below the manufactuer specs after the 5-10 mins, it's pretty safe to say you have a tight leak free system.

Most of the time, if there is leak in the system - it will show itself during the 5-10 min valve of period. This should NOT be used as a substitute for traditional leak checking.

[tech45]

I once was able to pull down to 100 microns ( Bluevac and Thermal analog connected ) and realized that there was a leak ( right near the service port I was connected to ). Pump isolation is the key .

[greg58]

One micron per minute is the acceptable leak rate I go by. That info came from JoeyD or Jim Bergman cant remember which. Either way

[71CHOPS]

If it rises above 1000microns within 10 min, you most likely have a leak......or refrigerant hiding in the system somewhere. I've heated compressors, lines, LLSV's and other parts with a heat gun to get all the refr. out. don't forget too, 410A with POE oil, you'll see a bit more rise as refr. boils out of the oil over time.....

also, if you can't pull below 1000, you most likely have a leak.

you have to have CRT's with the gauge connected to them or another access port, so you can isolate the system from your hoses/pump.