Where is a micron gauge placed when vacuuming system?

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atikovi
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Re: Where is a micron gauge placed when vacuuming system?

Post by atikovi »

Reads 310 this morning.
swampy 6x6
Posts: 59
Joined: Wed Dec 02, 2020 11:14 pm

Re: Where is a micron gauge placed when vacuuming system?

Post by swampy 6x6 »

hi
Always be observant when using vac pump . Look for fluctuations when operating taps .Also compare this to a new 1/4 hose with a micron gauge . If the readings are different the gauge set has a leak most likely . Vac both situations overnight to eliminate moisture as much as possible. If the microns keep rising every 15mins this suggests a leak . If the micron decay go up and level off probably moisture .

I use SAE 1/4 gauge line set which are easy to leak test as the R134a couplers are separate. VS the hoses that are screwed in to the couplers directly

R134a couplers can leak badly new o rings , use nylog on the manual tap threads / outside of the vehicle service fitting apply nylog / Ontop of tap handle [under sticker ] the spindle shaft has vacuum leaks ,apply nylog
This causes your gauge to struggle to pull down below 300--500 microns

As your leak testing ,, having a leaky gauge setup makes it useless and is first priority before position is considered

Both hoses connected in the suction line
1x hose on suction,,, gauge High slde connection
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