Mini-split Pressure Test/Evacuate Question

[DB2]

A question on mini split installation:

If I first pressure test a mini-split install with nitrogen, do I really need to use a micron gauge when evacuating the lines with a vacuum pump, or would simply running the vacuum pump for a few hours (and then verifying it holds -30" on a set of conventional gauges) be sufficient?

I have everything but a micron gauge...I'd like to do everything "right", but no sense in overkill.

 

[jad3675]

A question on mini split installation:

If I first pressure test a mini-split install with nitrogen, do I really need to use a micron gauge when evacuating the lines with a vacuum pump, or would simply running the vacuum pump for a few hours (and then verifying it holds -30" on a set of conventional gauges) be sufficient?

I have everything but a micron gauge...I'd like to do everything "right", but no sense in overkill.

I'd do it right and use a micron gauge. You can get a Fieldpiece SVG2 for $105 from testequipmentdepot.com.

John

 

[pop pop]

You'd be amazed at how porus your gauge set lines are and how much ref. is adsorbed in your vacuum pump oil that you'll never know....without the micron gauge.