Hoshizaki 73168 service manual Removal and Replacement of Refrigeration System Cartridge

B. Removal and Replacement of Refrigeration System Cartridge

CAUTION

The refrigeration system cartridge should not be removed until the refrigerant has been properly recovered or the refrigeration system has been properly pumped down. For refrigeration system repairs, the refrigerant recovery procedure must be used. See "IV.B.1. Refrigerant Recovery Procedure." For non‑refrigeration system repairs, see "IV.B.2. Pump‑Down Procedure." Do not discharge the refrigerant into the atmosphere.

1.Refrigerant Recovery Procedure

1)Remove the front panel. Move the power switch to the "OFF" position, then unplug the unit.

2)Remove the left side panel.

3)Connect the gauge manifold hoses to the receiver service valve (high-side) and the compressor access valve (low-side). See Fig. 1.

4)Run in the receiver service valve stem a couple of turns for high-side system access. Note: Be sure the high-side gauge manifold hose is on the receiver service valve

before opening the receiver service valve.

5)Using proper refrigerant practices, recover the refrigerant and store it in an approved container. Do not discharge the refrigerant into the atmosphere.

6)When the recovery is finished, close the gauge manifold valves and back out the receiver service valve stem all the way and tighten.

Note: Be sure the receiver service valve stem is backseated all the way out and tight.

7)Close the rail high and low-side service valves. Run in the rail service valve stems all the way until tight.

Note: Be sure the rail high and low-side service valve stems are seated all the way in and tight.

8)Disconnect the rail refrigerant tubes from the rail service valves. Use a backup wrench when loosening the fittings. See Fig. 1.

9)Remove the screw securing the rail service valve bracket.

10)Disconnect the power supply cord connector, rail thermistor connector, and the perimeter heater/rail fan motor connector.

11)Remove the wire cover below the control box.

12)Remove the upper and lower attachment nuts and washers from the control box and the hex head bolt from the base of the refrigeration cartridge. See Fig. 1.

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