R134a cooler

[captjake]

I got a true brand cooler. I put a new cap tube and filter drier. It's seems to be running ok but the low side seems to low.

The cooler holds a 10 oz charge r134a
I'm getting about 28 psi resting

When running the low side is 13 psi or 11 degrees F
High side 130 psi or about 100 degrees F
The evaporator was 20 degrees F

Cooler is holding good at 40 degrees F.

Cap tube is 12 ft of .064 in

Is the system still restricted? Is it ok to run it?

[joe magee]

What is the ambient around the unit? Sounds like it might be undercharged. What size drier? Larger then that strainer it came with. What are your splits? amp draw? What temp is the cooler when you have these readings? Cooler needs to be lower then 40 degrees, more like 34 to 36 degrees. When I have a cooler that I change a drier, cap tube etc I charge by suction and head pressure. Weighing the charge is just a starting point, you might have to adjust from there. Use a 30 degree split from ambient to converted head pressure as a start. Have a great day.

[FEISTY]

Hey captjake. My 2 cents is this. Don't overthink the problem. " It's True, It's True ". Sorry but that's the catch phrase we use in this area. Get your head to 150. Low side will level at about 20-22. Let the 134 run awhile to settle down. Best advice I ever got was from a seasoned veteran pal of mine who told me just what I told you and ended it with " walk away for awhile ". I am happy to say it has worked every time. As long as amps are close to specs without going over and your low side went up as you charged it thru high side you should have equalized at about 60 lowside in non-running mode. I do about 3 of these almost everyday and they normally smooth out and purr. Good luck and have a great day !

[FEISTY]

Hey captjake. I work on 4-6 of these units every week. Here is what works for me. Get head to 150. Suction should equal out at 20-22. As box drops to 35 degrees you should see 135 high 18-20 low. Best advice I ever got about 134 systems was...don't overthink them. Service it and step back for a bit. Let them settle in. It has always worked for me. When you charged it after pulling vacuum , your suction should have risen smoothly and landed about 60 before cycling on. If so, you should be fine. Using scale to load charge is great but remember part of the measured charge is in hoses. Depending on length you could end up shorting the charge by a couple of ounces thus undercharging the system. Try it and yell back. Good luck. Mind you this is only MY opinion. Others may have another thought.

[FEISTY]

Sorry guys. Another 13 hr day and I doubled my answer. Ignore 1st entry. Thanks

[Gary]

Hmmm... 28 psi = 32 F

The box is holding at 40F, but the coil is holding at 32F. Sounds like iced coil to me.

[captjake]

Thanks guys, I'm going to add more refrigerant. No ice on the evap. Both fans are working. I cleaned the evap when I had it apart. It's a pizza topping cooler. So I notice everything in back it colder than in front.

Thanks again, Jake

[captjake]

One other thing, I didn't have very good access to the evaporator. So I left about 8 inches of the old cap tube and brazed the new to old. But before I brazed it on I blew on it and had very good flow. And of course I removed 8 inches from the new cap tube.

[shamji]

i got a 30GTC carrier chiller.sometimes the compressor crank case is getting too cold.that time the suction pressure is 75 psi and discharge pressure 190 and oil is forming.can u help me from dis problem.?

[captjake]

Well changed the cap tube again, this time at the evap. Change the oil in the compressor (looked like ice tea). New filter drier.

It is 7 years old. It's in an hot enviroment near a 700 degree F pizza oven.

Overall the temp has improved and the compressor is not running all the time.

Hopefully no more clogs. Thanks for the help.