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Discussion Starter · #1 ·
Hey Guys., Been having trouble lately getting my meter to pull down.Last few jobs 1300-1700 best it will do. Did change oil on 6cfm pump recent and tested pump after.,think i had 250 microns. I do put the meter at service ports.,however i hook to those with 6ft hose back to gauges and pump. (hoses 1yr old).
I always pressure test systems with nytro.,so leaks should not be an issue.
Any thoughts would be appreciated.
 

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I'm not a tech., but have been around a long time. If you close off the line going to the pump, does it hold the vacuum? If it doesn't the problem isn't in the pump. If it holds, you either have a bad pump or not giving it time to pump down.
 

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If you’re sure it’s not leaks, then you could try cleaning the sensor in your micron gauge with isopropyl alcohol. It only takes a tiny bit of oil or moisture to contaminate the sensor so it won’t read correctly.
If that doesn’t work and you have a gauge with a replaceable sensor, then replacing it might be the next step.
If it’s one of those cheap Supco ones or something similar and cleaning the sensor doesn’t help, then it’s time for a new micron gauge.
 

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Discussion Starter · #4 ·
Thanks guys; It is a Subco,I have been little lax at cleaning tip,thanks for reminder. And yes it does "hold" when I shut off pump. Whats is a meter you would suggest to buy? $$?
 

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There are a lot of brands to choose from these days and prices are all over the place, but I think YJ 69086 is a pretty decent unit overall. It can often be found for under $200.00, if you shop around online.

http://www.yellowjacket.com/node/640
 

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Discussion Starter · #6 ·
Hooked set up directly to pump.,still 1850 microns had a short double female flaired fitting in set up., Replaces it., "410 microns!" may have had a crack in flair? Thanks again for the posts!
 

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Hey Guys., Been having trouble lately getting my meter to pull down.Last few jobs 1300-1700 best it will do. Did change oil on 6cfm pump recent and tested pump after.,think i had 250 microns. I do put the meter at service ports.,however i hook to those with 6ft hose back to gauges and pump. (hoses 1yr old).
I always pressure test systems with nytro.,so leaks should not be an issue.
Any thoughts would be appreciated.
Have you tried pulling down on a recovery cylinder as a controled test? I have found systems that didn't want to pull down past 700/1000 microns yet my pump would pull down a cylinder to 500 microns just fine. Possibly a combination of very small leaks in the system or moisture/refrigerant boiling off that is trapped in the oil, though that usually only decreases the vacuum over time rather than limit the initial pull.

ugh.. just noticed the post orientation is opposite from another site and didn't look at the post numbers lol
 

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not sure the model # but feildpiece has the combo manifold guages (digital) with a built in micron guage, among many other things. great set!
 
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