I bought an inexpensive ac vacuum pump & manifold kit . The red hose has a small brass fitting with holes in one end which I assume is an orifice . The blue hose didn’t have one in it but there was one laying in the box . The yellow hose doesn’t have any . I assume the red & blue hoses are supposed to have these orifices installed ?
Look inside the fittings. Any threads? The hoses have plunger fittings that push against schader valve to open/close the fitting. Not all the fittings have those bits. The manufacturer does not want you to hook up the hoses haphazrdly. Though some folks try too. They do sell adapters with acme threads for some applications. Are your gauges for R-22 or R-410 or automotive use?
This kit has quick connect fittings with on / off knobs that depress or release the schrader valves & connect where the schrader valves are . The hoses screw to these & to the manifold . The little orifice type things have threads & will thread into the hoses until snug .
I looked into the manifold holes to see if there was anything there for them to depress & there isn’t . There also isn’t anything in the holes in the quick connect fittings .
The kit is for R-134 A , automotive use . There are some adapters in the kit & it can be used for some other applications .
This kit is pretty much like what Harbor Freight sells , though I bought the kit off ebay . It is a new kit . The manual that come with it is totally useless . Chicken scratching & an extremely poor attempt at translation .
Post an image of this vacuum pump/gauge kit.
Some are totally useless.
I went ahead & installed the orifice or whatever it is in the other hose . Pulled a vacuum on the system for about an hour & it held . Charged the system & now have real cold ac .
I watched a few u-tube videos & in one of them I noticed the hoses the man was using had some type of fitting / orifice in them too .
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