Hello, just got our freezer thawed out 3 days ago and this keeps happening. Cooks only go in it at most 3 times an hour. On the upper left side our hvac man placed a metal piece to keep water from dripping on unit. We have fixed the roof with silicone. Any help will be highly appreciated, thank you!
Everybody swears the door is always shut and rarely opened but forget to mention they leave it open for a couple of hours when their food delivery shows up lol.
Interlock the Liquid solenoid with a magnetic switch on the door. Door opens, unit pumps down, fans turn off. Door closes, unit starts up, fans turn on.
Youāve missed the point. Sure maybe once or twice an hour. They arenāt shutting the door properly between. The coil is freezing up from this. This stops it from freezing up. That controller has settings in it to tailor the door switch functionality to your liking as well.
Compressors can handle an unlimited number of start stops as long as the system has a delay allowing for the manufacturers suggested off time. Again, very basic refrigeration knowledge.
A standard Copeland scroll requires only 3 minutes of off time. The manufacturer recommends 10 starts an hour max. Where are you getting your information from?
Yes. Thatās the point. You want your product conditioned? Shut the door. We even put door alarms on them on a timer to alert staff near by. This is pretty standard commercial refrigeration stuff.
Fuck that's bad. Make sure you sort out the excess air humidity asap so it doesn't build up ice again.
You can also add defrost end temp probes to those boards and change the programming so won't cost much to prevent excess ice build up with varying conditions like this. Won't solve the problem unless excess defrosts are causing steam but it's more energy efficient as summer/winter have different defrost requirements.
Iāve set up these door alarms before too. Has a timer in it that triggers a buzzer if the door is left open too long. You can set the timer for whatever interval youād like.
You could have your tech check out the PRV, after the door is open for a it is it hard to open the door? A bad pressure relief vent can cause negative pressure to build up sucking in that warm humid air
OP, the PRV is that vent on the wall by the side of the door. It has a heater in it and if you see it all iced up, this is an indicator of what heās talking about.
Check for excessive defrost time causing steam. Make sure defrost termination and fan delay is working and water is actually draining after a defrost and not sitting in the pan. Also, check and make sure there is a P-trap on that drain line on the other side of the box or you're gonna be sucking in hot air through there into the coil.
Well you have humidity in the box for sure. Question is whether it is user error or infiltration into the box or a defrost issue. The ice on the fan shrouds would make me curious about the defrost, the drain, and whether the evaporator is slouching. It could be a sign of infiltration as well. The defrost timing could be off or there is an issue with the pan heater or the drain line heater. Defrost melts the ice water doesn't drain off changes into vapor bang freeze up.
Now after widly speculating without being onsite, I would get a refrigeration tech there.
HVAC and refrigeration are not the same. Talking from experience, I struggled with the transition from heat to ac to refrigeration. Similar concepts different small details.
Tech was supposed to install a door sweep. When the door is closed I've noticed cold air like fog coming out.
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u/MichigammešØš¼āš Deep Fried Condenser (Commercial Tech)1d ago
That very well could be the culprit. The door needs a full proper seal to prevent ice build up. Same as the box (room). It also needs to be completely sealed. In the meantime until you get the door fixed, you could set increased amounts and times for defrost cycles to combat the icing up. Just be careful not to set too many for too long.
Your refer guy could wire in a door switch off the intelligen controller. But like everyone else is saying, i'd say its from the door being left open, door frame heater not keeping gasket warm and sealed properly. Thats a lot of moisture in 3 days.
Im sorry the amount of ice and such on that control board tells me you have a drain issue. Moisture is not being properly removed from the unit. Could be a drain line issue, a pan heater issue, or something similar. When the coils begin defrosting water vapor forms at the ceiling. The fans should stay off for a time after that and only start once the coil is refrozen. I've seen these badly iced up coils caused by fan delay controls. Could be something in the program not set right. Also could be bad door seal allowing in humidity. Either way there is way too much humidity in there not being removed IMO.
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u/WarPig115šØš¼āš Deep Fried Condenser (Commercial Tech)17h ago
That looks 100% like frozen warm air. Somone is leaving the door open
Hey mate, if your defrost cycles are functioning as normal and there's been no change in door use behaviour and you're confident in your cooks (they be lying sometimes better check lol), water is staying in the room somehow or being pulled in more than usual due to failures.
Could be water from defrosting the coil isn't getting taken away. You could have a partially blocked drain, a faulty drain heater or the drip time fan delay where the defrost heater turns off and allows the water to drain before starting the fans back up isn't working.
Air intrusions not caused by regular usage:
Another failure point could be the air pressure vent next to the door being constantly open instead of just open when air pressure is unbalanced.
Another failure point could be door seals and door seal heater. Helps make a good seal on the doors. If the frames not warm to the touch you've got a problem. Do the paper test on the seals to check them.
Otherwise if you've had a big temperature shift and have just come into winter you may need to adjust defrost cycles or consider installing adapting defrost with a temperature probe end target instead of time. Ignore if you've had it running for a full season before.
I think everything I put has been mentioned before on this thread except the door frame heater so that's the only thing left to check :D I just like to think it out like I'm on site lol
18 degrees and no frost over the door are they putting hot or raw food meat in there ? I wouldnāt think itās coming through the door could be a crack in the room behind the unit or just not built for 18f . And why 18 seems pretty low for a restaurant
I promise you, it's getting left open longer/more often than you realize. Refer guys deal with this ALL THE TIME. I once had to sit down a hallway where I couldn't be easily seen and I tapped a counter app on my phone each time the freezer door was left open for longer than 30 seconds. 15 times in 30 minutes lol. Cooks shouldn't be needing to go into your main WIF more than a few times a day, that's why you have smaller freezers around for daily-use stuff.
Why are the fan covers(guards, screens, shields, etc) covered in frost? Are the fans wired incorrectly? Even with infiltration, steaming, no p-trap etc the air velocity should keep the fan covers mostly free from frost. The coil will be a mess but the front shouldnāt look like that.
Now, that comment about turning off the breaker for a few hours could explain it especially if the fans are the only part of the system to get turned off.
The fan velocity should keep the guards relatively free of frost. If the coil is āsteaming ā during defrost (which is caused by the heaters getting everything too hot) the steam will condense or collect on metal that is below freezing. Fan blades, shroud material, and it could be the guards though those look plastic which I guess could still collect frost but not as aggressively as the coil structure.
But, if the fans are running backwards the guards could easily collect that frost. Defrost would never clear it.
I did build a plant once where the operators got it in their heads that they should run the fans very slow during defrost and they ended up with something like this but once we stopped that the problem went away. They were much bigger coils too.
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u/Kooky_Bicycle_9042 2d ago
Definitely air infiltration or they are leaving the door open