undersized liquid line

[slonergan82]

I was working on a 10 ton high temp potato cooler the other day. The liquid line is 5/8 for about 8 feet and tees off to 2 evaps with 5/8 line aswell, each at about 8 feet. The gas is 404 (request of the customer) When charging the system I couldnt clear the sightglass ended up putting way too much gas in and had to pull some out the next day. My question is If the liquid line is undersized would I see flashing in the sightglass up at the condensing unit?
I know an undersized liquid line causes pressure drop and therefore may cause flash gas at the txv but I dont see why you would see flashing upstream of the undersized liquid line where the pressure drop hasnt occurred yet? Im sorry I am not giving alot of info just more of a general question.

[jpsmith1cm]

I was working on a 10 ton high temp potato cooler the other day. The liquid line is 5/8 for about 8 feet and tees off to 2 evaps with 5/8 line aswell, each at about 8 feet. The gas is 404 (request of the customer) When charging the system I couldnt clear the sightglass ended up putting way too much gas in and had to pull some out the next day. My question is If the liquid line is undersized would I see flashing in the sightglass up at the condensing unit?
I know an undersized liquid line causes pressure drop and therefore may cause flash gas at the txv but I dont see why you would see flashing upstream of the undersized liquid line where the pressure drop hasnt occurred yet? Im sorry I am not giving alot of info just more of a general question.

Did the glass ever clear?

I just had a BAD problem that was detailed in the PRO section with a system that would NEVER have cleared the glass.

Not sure about the line sizing, but it isn't the first thing that I would look at.

[sarpanch2001]

5/8
right size for 10 ton according to URI catlog

[slonergan82]

5/8 line feeding two 5/8 lines doesnt seem right. You should always have a larger line feeding a tee no?

[270wsm]

Did the glass ever clear?

I just had a BAD problem that was detailed in the PRO section with a system that would NEVER have cleared the glass.

Not sure about the line sizing, but it isn't the first thing that I would look at.

Can you post a link to that "BAD" problem so i can read about it?:)

[gatorfan9606]

I was working on a 10 ton high temp potato cooler the other day. The liquid line is 5/8 for about 8 feet and tees off to 2 evaps with 5/8 line aswell, each at about 8 feet. The gas is 404 (request of the customer) When charging the system I couldnt clear the sightglass ended up putting way too much gas in and had to pull some out the next day. My question is If the liquid line is undersized would I see flashing in the sightglass up at the condensing unit?
I know an undersized liquid line causes pressure drop and therefore may cause flash gas at the txv but I dont see why you would see flashing upstream of the undersized liquid line where the pressure drop hasnt occurred yet? Im sorry I am not giving alot of info just more of a general question.

what are your pressures? compressor info would be nice to along with amps

[HVAC9900]

Do you have any subcooling?
What is the superheat?

[Dowadudda]

torch the receiver.

[jpsmith1cm]

Can you post a link to that "BAD" problem so i can read about it?:)

http://hvac-talk.com/vbb/showthread.php?t=321062

Here you are.

[jpsmith1cm]

torch the receiver.

x2.

Excellent place to start. :)

[Dowadudda]

5/8 line feeding two 5/8 lines doesnt seem right. You should always have a larger line feeding a tee no?

if it was being choked, the liquid would stack and so at the glass you'd be full Column.

I am telling the guy to torch the receiver because the dip tube is most likely broke. He is filling and filling and not clearing. And then took some out the next day when ambient went up.

[Dowadudda]

Undersized liquid line would have the same effect as choking it at a tee. You'd be full at the glass. You'd flash down stream and high superheat.

[icemeister]

There's nothing fundamentally wrong in oversizing a liquid line and if it were oversized it definitely wouldn't have any bearing on the problem you're seeing.

I agree with JP and Dow on this one. Torch the receiver and you should have the answer. ;)