PDA

View Full Version : wet sight glass



trammd
26-02-2002, 05:29 AM
I have just purchased 2 larkin scroll outdoor cond. units that have been supposedly factory charged and pressurized with "dry air"
here is my dilema, on both sealed units the Alco refrigeration sightglasses read wet "yellow" these are brand new units "never run". Shouldnt the sightgjlasses read dry(green)?? There is pressure at the suction and liquid line schraders.

why are they reading wet??

Frosty
26-02-2002, 08:44 PM
Hi

Never heard of manufacturers charging with dry air. Its standard practise to charge with Nitrogen and leave a slight positive pressure.

Maybe the manufacturer has charged with 'dry air' but carried out an ineffective evacuation procedure beforehand? Who knows, the fact remains that, yes you do have a wet system.... thats presuming that the S/G is open to the system?

Best bet is to change the drier and evacuate the system (preferably a triple evacuation) before running the system.

Cheers

Frosty :D

Prof Sporlan
27-02-2002, 12:04 AM
The Sporlan moisture/liquid indicator will change color in the range of 0.5 to 2.0 percent RH and a similar range would be true of Alco's. 70°F dry bulb air at a 2 percent RH has a -17°F dew point, so one would have to use very dry air to prevent the moisture/liquid indicator from changing color.

You probably don't have much to worry about, though a good evacuation and installing a filter-drier should be in order... :)