My friend has an under counter Norlake UF72 unit.
I checked it out and everything seems to be running fine but it doesn't seem to be cooling as well as it should be.
Any tips to get this unit running at 100% capacity?
What are your pressures? This unit I believe is a 134-A cap tube system. If this unit has run hot from a clogged condenser coil for a period of time you could have a partially restricted cap tube. Very common on 134-A systems. Your efficiency will be affected. It is most likely reaching a certain temp and not dropping any lower. During heavy traffic use of the box with doors being opened constantly, it will struggle to recover and actually go up in temp. Replace it with the OEM cap tube. Make sure the condenser coil is really clean internally, not just brushed. Check with a flashlight to see if light passes through easily. Worn valves, if system is fully charged check RLA on the compressor. Non condensables in the system are also possible. Recover system, pull a full 500 micron vacuum and recharge per data plate. If it is a partial restriction you won't have much heat transfer. I have limited info on your friends unit here but if its running and not efficient, these things in my experience will be likely at fault.
I Couldn't have put it better. Very thorough.
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