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E. Removal and Replacement of Evaporator
IMPORTANT
Always install a new drier every time the sealed refrigeration system is opened.
Do not replace the drier until after all other repairs or replacement have been
made.
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 "U" shaped notch where the
refrigeration tubing passes through the molded chassis.
5) Disconnect the evaporator tubing.
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. See the nameplate for the required
refrigerant charge.
12) Replace the removed parts in the reverse order of which they were removed.
13) Replace the front and top insulation and the panels in their correct positions.
14) Turn on the power supply.
