problem on a walkin freezer today. running warm about 40f. 360psi head 15 psi suction. R-404a. No reciever TXV system.
Between top of box and cieling approx 2 and a half foot. with both walkings next to eachother in maybe 12ft from wall to wall walking in cooler walk through to freezer. Both boxes are packeged condenser and evaporator on top of the box. return and supply next to eachother in ceiling of box. No sight glass on system but an alco pressure limiting TXV no CRO valve, electric defrost.
Feel discharge line very very hot with a very warm liquid line, quickly rinse of condenser (construction dust), head pressure comes down slightly but still hot. all fans running condenser and evaporator, notice ice build up at inlet of evaporator hose out evaporator, remove ice.
little temp drop across filter drier decide to add a little gas just in case its low on gas but because of dirty condenser and recirculating air raising head. No increase in suction and coil is still not flooding out.
Decide to install a new TXV external equalized with a KT-43-RZP head, filter drier 0163s, and a sight glass. Vacuum down and leak check. GOOD.
So i weigh in a charge but adjust so my sight glass just clears itself. box is starting to drop but still not flooding out coil completely. Even with ZP charge head im reading suction 30 psi approx -5f with about the same head pressure as before. Suction pressure does start to drop but have to leave. Box was at 20f when i left with the coil still not flooding.
My boss told me to tell them to check on it in the morning to see if it came down all the way. I left there about 4 ish, so let it run through the night.
Sorry no mod or serial numbers.(meant to get but had to run).
Really hoping I have not missed anything pressure limiting TXV's have blowen my mind today. Will the box take its time coming down to temp because of ZP head. Any ideas. THanks