Carrier 38MBRC Series Service Manual page 20

38MBRC: Service Manual
REMARKS:
• Use a multimeter to test the DC voltage between the 2 port (or S or L2 port) and the 3 port (or N or S port) of the outdoor unit.
• The red pin of the multimeter connects to the 2 port (or S or L2 port) while the black pin is for 3 port (or N or S port).
• When the air conditioner is running normally, the voltage is moving alternately as positive values and negative values.
• If the outdoor unit malfunctions, the voltage has always had a positive value.
• If the indoor unit malfunctions, the voltage has always had a certain value.
• Use a multimeter to test the reactor resistance which does not connect with a capacitor.
• The normal value should be around zero ohm. Otherwise, the reactor has malfunctioned.
NOTE: Images and the values inside are for reference only. Actual condition and specific value may vary.
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
L2 and S
20
S and N
or
or
2 and 3