D. Removal and Replacement of Drier
IMPORTANT
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)Unplug the unit from the electrical outlet.
2)Remove the panels.
3)Recover the refrigerant and store it in an approved container.
4)Remove the drier, then place the new drier in position. Install the new drier with the arrow on the drier in the direction of the refrigerant flow.
5)Braze all fittings while purging with nitrogen gas flowing at a pressure of 3 to 4 PSIG.
6)Check for leaks using nitrogen gas (140 PSIG) and soap bubbles.
7)Evacuate the system, and charge it with refrigerant. See the nameplate for the required refrigerant charge.
8)Replace the panels in their correct positions.
9)Plug the unit back in.
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)Unplug the unit from the electrical outlet.
2)Remove the panels.
3)Recover the refrigerant and store it in an approved container.
4)Remove the insulation and the expansion valve bulb on the suction line.
5)Remove the expansion valve cover and disconnect the expansion valve. 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.
WARNING
Always protect the valve body by using a damp cloth to prevent the valve from overheating. Do not braze with the valve body exceeding 250°F (121°C).
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