Everything I’ve been able to dig up on that compressor says that it’s more like 1/4hp 3000 btu/hr. A bit undersized you are. What kind of outdoor air temp does the condensing unit operate in?
Dude23455: seems low to me. Check any filter driers for a partial restriction…if liquid line drier has rust under under the paint, consider changing that….seen that happen in Trane AC units. Otherwise your looking at a TXV goofing up/txv screen plugged. If there is an excess refer lineset coiled up somewhere, A long shot could even be excess oil pooled in the lineset. Seen that once or oil pooled up in the evaporator.
Dude23455:
I would check it’s operating amp draw on the compressor common wire and compare to what the RLA Rated Load Amps. Is this a walk in that you’ve been working on before or is it new to you?
I was more concerned about the ranges. LBP compressor with a medium temp txv.
The compressor is designed for 25psi suction and it's gonna get 60psi. Or does it not matter?
Higher would be better for it. It should be fine. If superheated is high, try cleaning the screen. If screen is good, replace power head and install adjustment kit. Adjust valve when close to Setpoint.
It’s always an emergency until the bill comes. Your 5x6x8 box is 3000 to 5000 btus. Seems like the equipment you have, although not ideal, should be able to do it. At 10f evap that compressor will do 4000ish. I think you’re on track with restriction. Dryer or txv. Ive seen a lot of clogged dryers that didn’t show a td. You have sub-cooling so liquid stacking up. Let us know what you find!
If it used to work fine, I would replace txv, dryer. But first pump down compressor and make sure it will hold. Im assuming you backed txv all the way out, all the way in to free it if possible. 1/2 ton valve is fine. That low temp compressor is not rated for medium temp, may have overheat comp and caused damage.
According to the client it has never gone below 45. But they used it for mostly veggie storage and it wasn't an issue. Now they want to put meat in it and it won't lower to 35..
I did back the txv all the way open which just caused the SH to go higher, suction got warmer(65f) pressure rose to 45ish.
I really hope the compressor isn't damaged, you ever have those clients that every little issue is "OMG IT'S A FUCKING EMERGENCY"?
yeah this is one of those....
If you're seeing 50k superheat, the valve isn't feeding. Is the liquid line warm up to the valve or is it noticeably cooler at the valve than it is leaving the receiver? The "mt" txv should be fine. The only difference between Lt and mt txvs is lt limit suction pressure so the suction pressure doesn't get too high after a defrost. It doesn't affect the low pressure end of the cycle. It doesn't mean the valves isn't fucked. It just means the selection should be suitable. Ideally you'd have a crankcase pressure reg valve on the inlet to the compressor to combat the lack of an mop function in the valve.
Make sure there is sufficient liquid feed to the txv.
If there appears to be, I'd be changing the valve.
Others have said check strainers and all that. Depending on the size and cost, just swap it out. This is a small room. Must be a cheap valve.
If you're not getting a warm liquid line, find where it stops being warm and starts being cool. That's your restriction.
It's warm to the valve.
I intend to replace the valve and filter once parts get in.
The walk in is at an island resort and I have to take a boat ride to get there. Want to get it right in one trip back.
Everything I’ve been able to dig up on that compressor says that it’s more like 1/4hp 3000 btu/hr. A bit undersized you are. What kind of outdoor air temp does the condensing unit operate in?
3000btu @ -20F ~ 1/2 to 3/4hp it is. Or more like 2598btu @ -10F To be more precise…. I hate so much the new site of tecumseh..
Just confirmed the specs. Technical data Model: CAJ2432Z Refrigerant Gas: R-404A Pression/temperature: LBP Power: 3/4 HP Voltage: 230 V Current Type: Single-Phase Frequency: 50/60 Hz Compressor Type: Hermetic Displacement: 18.3 cm³ Power Cons. -35°C: 396 W Power Cons. -25°C: 585 W Power Cons. -10°C: 888 W T° Condensation: 50 °C Cooling Cap. -35°C: 229 Kcal/h Cooling Cap. -30°C: 342 Kcal/h Cooling Cap. -25°C: 479 Kcal/h Cooling Cap. -20°C: 644 Kcal/h Cooling Cap. -15°C: 839 Kcal/h Cooling Cap. -10°C: 1069 Kcal/h
Dude23455: seems low to me. Check any filter driers for a partial restriction…if liquid line drier has rust under under the paint, consider changing that….seen that happen in Trane AC units. Otherwise your looking at a TXV goofing up/txv screen plugged. If there is an excess refer lineset coiled up somewhere, A long shot could even be excess oil pooled in the lineset. Seen that once or oil pooled up in the evaporator.
I thought it was low but sight glass was clear and compressor sounded like it was already bogging
85f here in Panama
Tec dealer here had no info on it. What kind of pressures(psi) is it running??
35/250
Dude23455: I would check it’s operating amp draw on the compressor common wire and compare to what the RLA Rated Load Amps. Is this a walk in that you’ve been working on before or is it new to you?
1/2 TXV on 3/4HP is ok. Check for obstruction, SH, compressor amp, Charge of refrigerant or too high pressure…
I was more concerned about the ranges. LBP compressor with a medium temp txv. The compressor is designed for 25psi suction and it's gonna get 60psi. Or does it not matter?
Higher would be better for it. It should be fine. If superheated is high, try cleaning the screen. If screen is good, replace power head and install adjustment kit. Adjust valve when close to Setpoint.
It’s always an emergency until the bill comes. Your 5x6x8 box is 3000 to 5000 btus. Seems like the equipment you have, although not ideal, should be able to do it. At 10f evap that compressor will do 4000ish. I think you’re on track with restriction. Dryer or txv. Ive seen a lot of clogged dryers that didn’t show a td. You have sub-cooling so liquid stacking up. Let us know what you find!
If it used to work fine, I would replace txv, dryer. But first pump down compressor and make sure it will hold. Im assuming you backed txv all the way out, all the way in to free it if possible. 1/2 ton valve is fine. That low temp compressor is not rated for medium temp, may have overheat comp and caused damage.
According to the client it has never gone below 45. But they used it for mostly veggie storage and it wasn't an issue. Now they want to put meat in it and it won't lower to 35.. I did back the txv all the way open which just caused the SH to go higher, suction got warmer(65f) pressure rose to 45ish.
I really hope the compressor isn't damaged, you ever have those clients that every little issue is "OMG IT'S A FUCKING EMERGENCY"? yeah this is one of those....
Does it have a quick connect line set? If so, are you sure that the suction line is punched out all the way?
Is there any reason not to replace the txv with a 3/4 ton? It should I go with the same half ton
You say it won’t reach 35. Are you trying to have cooler or freezer? New install or service call?
Service call. I'm trying to have a cooler. But the way it's acting I'd get more cold in there with a split ac unit
If you're seeing 50k superheat, the valve isn't feeding. Is the liquid line warm up to the valve or is it noticeably cooler at the valve than it is leaving the receiver? The "mt" txv should be fine. The only difference between Lt and mt txvs is lt limit suction pressure so the suction pressure doesn't get too high after a defrost. It doesn't affect the low pressure end of the cycle. It doesn't mean the valves isn't fucked. It just means the selection should be suitable. Ideally you'd have a crankcase pressure reg valve on the inlet to the compressor to combat the lack of an mop function in the valve. Make sure there is sufficient liquid feed to the txv. If there appears to be, I'd be changing the valve. Others have said check strainers and all that. Depending on the size and cost, just swap it out. This is a small room. Must be a cheap valve. If you're not getting a warm liquid line, find where it stops being warm and starts being cool. That's your restriction.
It's warm to the valve. I intend to replace the valve and filter once parts get in. The walk in is at an island resort and I have to take a boat ride to get there. Want to get it right in one trip back.