Once a week, a call will come in that the cooler temp is at 50 degrees. It is a longer run walk in so add just a touch of refrigerant (404) to keep it from short cycling.
Everything runs fine for 45 minutes and all of a sudden, suction pressure drops and will not rise. Jump out low pressure switch and let it run for a few seconds, and again pressure does not rise, like it is in pump down.
Removed the TXV bulb and held it in my hand for a minute, no rise in pressure. The workers were moving the items out of the way when my shift was up, but I'm thinking the TXV maybe clogged or stuck closed as I have gotten this call 2 times, but never enough time to troubleshoot it.
But I have heard from co workers that the pressure will all of a sudden rise and the system will work normal again. Just not sure if it is the TXV or the Liquid line solenoid that is failing as I never have enough time to access the panel to check out the components.