American Aldes DHV-150H Refrigerant Charging, Fan Replacement, Compressor/Capacitor Replacement

6.Turn on the fan switch; the fan should run. Turn off the fan switch.

7.Turn on the humidity control; the compressor and fan should run.

8.If these tests work, the problem is most likely in the field control wiring.

5.4 Refrigerant Charging

If the refrigerant charge is lost due to service or a leak, a new charge must be accurately weighed in. If any of the old charge is left in the system, it must be recovered before weighing in the new charge. Refer to the unit nameplate for the correct charge weight and refrigerant type.

5.5 Fan Replacement

The motorized impeller is a unitary assembly consisting of the motor and impeller. If defective, the complete assembly must be replaced.

1.Unplug the power cord.

2.Remove the cabinet access panel.

3.Remove the screw attaching the fan support bracket to the base.

4.Disconnect the fan leads inside the electric box.

5.Push up on the inlet ring and pull the fan and fan support bracket to the right, then up and out of the unit.

6.Remove the defective fan from the bracket and replace with new fan.

7.Reassemble the new fan by reversing the above procedure.

5.6Compressor/Capacitor Replacement

This compressor is equipped with a two terminal external overload and a run capacitor, but no start capacitor or relay (See Figure 4).

CAUTION-ELECTRICAL SHOCK HAZARD: Electrical power must be present to perform some tests. These tests should be performed by a qualified service person.

5.6A Checking Compressor Motor Circuits

Perform the following tests if the fan runs but the compressor does not with the fan switch and ventilation timer OFF and the humidity control ON.

1.Unplug the unit; remove the cabinet side and the electrical connection cover on the compressor top.

2.Plug in the unit and turn the humidity control to ON. Check for 110 volts from compressor terminal R to overload terminal 3 using an AC voltmeter. If voltage is present, go to step 3. If no voltage, there may be a loose connection in the compressor circuit. Test each component for continuity. See the appropriate section if a defect is suspected.

3.Unplug the unit, and then disconnect the red and yellow wires from compressor terminals R & S. Using an ohmmeter check continuity between the points listed below.

4.Compressor terminals C and S:

No continuity indicates an open start winding. The compressor must be replaced. Normal start winding resistance is 3 to 7 ohms.

5.Compressor terminals C and R:

No continuity indicates an open run winding. The compressor must be replaced. Normal run winding resistance is .5 to 2 ohms.

6.Compressor terminal C and overload terminal 1: No continuity indicates a defective overload lead.

7.Overload terminals 1 and 3:

If there is no continuity, the overload may be tripped. Wait 10 minutes and try again. If there is still no continuity, it is defective and must be replaced.

8.Compressor terminal C and compressor case: Continuity indicates a grounded motor. The compressor must be replaced.

9.Disconnect the wires from the run capacitor. Set the ohmmeter to the Rx1 scale. The capacitor is shorted and must be replaced if continuity exists across its terminals. If there is no needle movement with the meter set on the Rx100000 scale, the capacitor is open and must be replaced.

10.Reconnect the wires to the compressor and capacitor. Plug in and turn on the unit. If the compressor fails to start, replace the run capacitor.

11.If the unit still does not start, adding a hard-start kit (relay & capacitor) will provide greater starting torque. If this doesn't work, the compressor has an internal mechanical defect and must be replaced.

5.6B Replacing a Burned Out Compressor

The refrigerant and oil mixture in a compressor is chemically very stable under normal operating conditions. However, when an electrical short occurs

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