Hoshizaki KM-901MWH - Manual (Page 73)

73
10) Evacuate the system, and charge it with refrigerant. For air-cooled and water-cooled
models, see the nameplate for the required refrigerant charge. For remote air-cooled
models, see the rating label inside the icemaker.
11) Replace the solenoid in its correct position.
12) Replace the panels in their correct positions.
13) Turn on the power supply.
E. Removal and Replacement of Evaporator
CAUTION
1. Always install a new drier every time the sealed refrigeration system is
opened.
2. Do not replace the drier until after all other repair or replacement has been
made. Install the new drier with the arrow on the drier in the direction of the
refrigerant flow.
3. When brazing, protect the drier by using a wet cloth to prevent the drier from
overheating. Do not allow the drier to exceed 250°F (121°C).
1) Turn off the power supply.
2) Remove the panels and the front and top insulation.
3) Recover the refrigerant and store it in an approved container.
4) Remove the spray tubes. Remove the insulation at the notch where the refrigeration
tubing passes through the molded chassis.
5) Disconnect the evaporator tubing.
Note: The pipes in the evaporator case are specially coated to resist corrosion. Use
sandpaper to remove the coating from the brazing connections before unbrazing.
6) Remove the pop rivets securing the evaporator, then lift out the evaporator.
7) Install the new evaporator.
8) Remove the drier, then place the new drier in position.
9) Braze all fittings while purging with nitrogen gas flowing at a pressure of 3 to 4 PSIG.
10) Use an electronic leak detector or soap bubbles to check for leaks. Add a trace of
refrigerant to the system (if using an electronic leak detector), and then raise the
pressure using nitrogen gas (140 PSIG). DO NOT use R-404A as a mixture with
pressurized air for leak testing.
11) Evacuate the system, and charge it with refrigerant. For air-cooled and water-cooled
models, see the nameplate for the required refrigerant charge. For remote air-cooled
models, see the rating label inside the icemaker.
12) Replace the removed parts in the reverse order of which they were removed.
13) Replace the top insulation and the panels in their correct positions.
14) Turn on the power supply.