Finishing off vacuum - how to remove gauge?

[Reptile]

Hello

Just finishing off my first install of a mini split. I've done everything by the book, and am currently sat at 300 microns vacuum with a digital gauge inbetween the service port and the manifold gauges.

Just a bit confused as to how to finish off? I'm guessing the vac gauge won't like pressure too much, so i need to get it out before I release the refrigerant... how best to do it?

Just pop the whole lot off now, and release the refrigerant unmonitored? But won't the vacuum be ruined when I release?

Or, break it off, refit the manifold gauges and pump, and re-pump for a further half hour or so?

Or, release refrigerant slowly up to a certain (low) pressure, then disconnect?

Any advice appreciated.

[nike123]

Digital vacuum gauge is termocouple element and it is not afected with pressure in system. Release refrigerant until you see positive pressure at manifold gauges (cca 1barg) and then remove digital vacuum gauge.
However, it is affected by oil in system and now is good time to clean it with alcohol.

[Grizzly]

Alternatively next time use a 5 port manifold.
Or one with these dual flare fittings.
Where 1 has a schraeder fitting.
Either way it is best to be able to remove the vacuum gauge, prior to system pressurisation.
Grizzly

[Reptile]

Just to say thanks guys. Success.