R-22 walk in cooler

[frankie89]

hi all,
i came across a walk in cooler using R22 but ive never worked on one before, what are the operating pressures? i add r22 up to 50 psig but wouldn't go above that then came the rain and i haven't been able to go back to it. thx

[Six]

Arw you monitoring liquid subcooling and suction superheat and consulting a PT chart ? Or are you just adding R22 until you see familiar pressures ?

Doing the lattter could be a waste of expensive R22. Also Im assuming their is a reciever on that cooler and a head pressure control valve.

Depending on ambient temp you might have to restrict air flow through the condensor to increase liquid saturation temp to 120 degrees to properly charge it.

Consult your PT chart for corresponding pressure.

My R22 walkins maintain 34 to 38 degrees with a delta of around 10 to 15 degrees.

Hope this helps.

[valdelocc]

48-50psi is about right, like anything else, clear the sight glass, check superheat and supcooling.

[craig1]

Is the condenser indoors or outdoors?

[socotech]

Was it a "hot pull down"? My experience with walk-N is a considerably higher suction pressure during a hot pull down. After box temp gets down to around 45*, the press will be lower.

[Dchappa21]

All you need to do with refrigeration is FILL THE GLASS! It's not as hard as AC work.

[jpsmith1cm]

All you need to do with refrigeration is FILL THE GLASS! It's not as hard as AC work.

Well, that assumes that it doesn't have a headmaster.


Subcooling doesn't matter a lot with refrigeration work.

Solid column of liquid, verified by a sightglass. SET the superheat on the TXVs.

[2sac]

Did you find/fix the leak?

[VTP99]

All you need to do with refrigeration is FILL THE GLASS! It's not as hard as AC work.

Wow.....I would think the opposite. I do both and find refrigeration to be much more challenging.

[Dchappa21]

Well, that assumes that it doesn't have a headmaster.


Subcooling doesn't matter a lot with refrigeration work.

Solid column of liquid, verified by a sightglass. SET the superheat on the TXVs.

I'm guessing he isn't going to need to flood the condenser very much in Laredo Texas. LOL... But yes if you have a headmaster you should add your winter charge.
http://www.sporlanonline.com/90-30-1.pdf

[Six]

All you need to do with refrigeration is FILL THE GLASS! It's not as hard as AC work.

Flashing or bubbles in a SG can be caused by other issues and if I remember correctly some blends in refrigeration applications can still bubble even when the unit is charged correctly.

[jpsmith1cm]

I agree with Dchappa.

HVAC is crazy.

Refer work is simple 99.8% of the time.

It's the 0.2% that makes my paycheck, though......

[Dchappa21]

Wow.....I would think the opposite. I do both and find refrigeration to be much more challenging.

I was trying to be sarcastic. I do both as well.