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E. Removal and Replacement of Expansion Valve
IMPORTANT
Sometimes moisture in the refrigeration circuit exceeds the drier capacity and
freezes up at the expansion valve. Always install a new drier every time the
sealed refrigeration system is opened. Do not replace the drier until after all
other repair or replacement has been made.
1) Remove the refrigeration tray as outlined in "V.C. Removal of Refrigeration Tray."
) Recover the refrigerant and store it in an approved container.
3) Remove the insulation and the expansion valve bulb on the suction line.
4) Remove the expansion valve cover and disconnect the expansion valve.
5) Place the new expansion valve in position.
6) Remove the drier, then place the new drier in position.
7) Braze all fittings while purging with nitrogen gas flowing at a pressure of 3 to 4 PSIG.
CAUTION
Always protect the valve body by using a damp cloth to prevent the valve from
overheating. Do not braze with the valve body exceeding 50°F (11°C).
8) 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.
9) Evacuate the system, and charge it with refrigerant. See the nameplate for the required
refrigerant charge.
10) Attach the expansion valve bulb to the suction line in the same location as the previous
bulb. The bulb should be at the 1 o'clock position on the tube. Be sure to secure the
bulb with the clamp and holder and to insulate it.
11) Place the expansion valve cover in position.
1) Replace the refrigeration tray in the reverse order of which it was removed.
CAUTION
1. When reinstalling the refrigeration tray, make sure the drain hoses align
properly over the drain tank in the rear of the machine. See Fig. .
. Make sure wiring is properly secured by the wire saddle and clear of the fan
blade.
13) Replace the lower cabinet stand panel in its correct position.
14) Plug the icemaker back in. Move the control switch to the "ICE" position to start the
automatic icemaking process.
