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Melvyn
04-09-2014, 10:14 PM
Hi everybody I am new to refrigeration as I am to this forum. I am F-gas qualified and registered with Refcom. I have a problem with a double upright commercial freezer. It as no manufactures name on it but says FO-1300-DEZ on the label. It as been looked at by a company but is still only getting down to -16c and hence the compressor is running constantly. There is a build up of ice under the lagging from the evaporator to the compressor but this could be due to the compressor not turning off. The evaporator fan is working but appears a bit week but I am unable to access it to inspect it or the evaporator. The condenser is acceptably clean and the fan is working fine. The freezer is in a kitchen and the ambient temp was 26c. The surface temp of the suction line at point of entry to the compressor when the freezer is at -12c is 8c and the high side at point of exit is 101c. The temp at POEntry to the condenser is 56c (the pipework runs around the cabinet first dissipating half of the heat) and 30c at POExit and POEntry to the filter/drier. There is a 1 degree increase at the output of the filter at the capillary and a 5 degree reduction to 26c at the end of the coiled capillary where it disappears under the lagging. The unit uses 700g of R404A and the gauge readings are low side 23.2psi -23.6c (which doesn't add up) and the high side 271psi 43.2c. Any advice would be appreciated. Many thanks, Melvyn

Glenn Moore
05-09-2014, 03:25 PM
Hi Melvyn
I would first totally defrost the cabinet and allow the insulation to dry out.Once you have done that turn the cabinet back on and check Ps and Ts around the system. If the insulation is damaged or saturated this acts as a heat sink and the cabinet will never reach temperature as youve experienced. This type of problem can occur during the foaming of the insulation process of the cabinet. If the insulation doesn't fully fill the cabinet cavity then the insulation is compromised, and will lead to ice formation leaking through the insulation. Give it a go but if the ice returns it may required re foamimg of the cabinet or the graveyard br Glenn