ReplyIf the SC looks good and the glass is still flashing, stop charging. You are more concerned with the SC than the sight glass.
Professional Member
when charging a walk in freezer, is it ok to charge to a full sight glass. there isnt a receiver. 404a.
Professional Member
If the SC looks good and the glass is still flashing, stop charging. You are more concerned with the SC than the sight glass.
Professional Member
I've been told by my more learned colleauges that a system with txv and no reciever is pretty sensitive to charge. If it's not in right temp area. Charge'til it almost no flash. When close in themp it will stop flash and become clean sight glass. This is what i've performed on a pair of coolmax freezer units w/no reciever. Success every time. Ah... Subcool... let it be 'bout 5-6degF
Professional Member
I dont use site glass for anything!
Professional Member
No receiver, that could be a problem when it satisfies and pumps down. It does pump down, right?
Professional Member
That would depend on a number of factors.Originally Posted by bigger b
Length of the liquid line being pumped down would be the biggest.
Professional Member*
Walk in freezer with no receiver? Flashing sight glass is OK? Umm no!! TXV must have full colum of liquid. You cannot adjust TXV to proper superheat with out a full colum of liquid feeding it. It will hunt and never stabilize. Are you sure there is not a receiver?
Regular Guest
reason number 1 why manufacturers are getting rifd of sight glasses, people rely on them. weed out the non-professionals
Regular Guest
at least thats what all of the trade-show guys keep preaching to us and it seems to make sense.
Professional Member*
I disagree with that statement. So if you mis-interpret your meter, you should not use it anymore? Sight glasses have their place and their purpose and refrigeration work is where you'll see them the most.
Professional Member
Very bold statement to be making.
Got proof?
Regular Guest
well, companies that use sporlan and danfoss told us that's why manufacturers are *trying* to do away with them on their systems. maybe not weed out the suckers like i mis-spoke, but to try to differ people from relying on them i should have said.
Regular Guest
to quote national: "Do not replenish refrigerant solely because of bubbles in the sight glass. First find out the cause of the bubbles!" I'm thinking fractionization has an additional effect.
Professional Member
There is a time to rely on a sightglass and a time NOT to rely on a sightglass.
A professional knows the difference.
Professional Member*
Humor me and explain this a bit further please..... I'm with jp, someone who knows what they are doing will know what to do with it. You can't make our industry idiot proof no matter how hard they try to. Everyone of us works with someone or knows someone that proves that point.
Professional Member
I am not a 404a expert by any means!!!
But i do not think that any fractionization would be taking place in a 98* liquid line that is 100%liquid refrigerant subcooled 12*.
Just sayin!
I will look at the bubble point and come back.
After i watch the voice with my daughter.
Professional Member*
You will do your homework during the commercial break and like it!!!!
Professional Member
There's a lot of variables to your question.
More specifics would be needed for your exact situation.
It's very possible that you need to leave the sight glass flashing & add a liquid/suction heat exchanger near the TEV.
Professional Member
ROFL!!!!!!!!!!!!!!!!!
true knowledge exists in knowing that you know nothing.
Professional Member
if you charge to full sight glass you take good chance on a overcharge if you have a txv and the box is warm . i like sight glasses use full,
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