Troubleshooting - Electro Industries EM-MC00 Series Installation & Operating Manual

NOTE
PORTIONS OF TROUBLESHOOTING AND FOLLOWING FLOW CHART WILL NOT APPLY TO THESE
NO HEAT MODELS.
1. This product contains several interference suppression components, but as an electronic logic
product unpredictable and unusual transients or interferences may sometimes cause strange
results. If this product is "acting strange", turn off the source power, count to 10, and reenergize.
2. Terminal blocks are clamp-down type. If there is no wire connected and the screw is loose, the
screw may not necessarily make a good electrical contact to the inside components. Example – if
you are jumpering the thermostat terminals without thermostat wire connection or if you are
attempting to measure voltage on a screw head, you may get erroneous or unpredictable results if
the screw is not tightened down.
Temperature Sensors
The inlet sensor is used to determine the incoming air temperature. The incoming air temperature
information is used in conjunction with the outlet sensor by the software.
Troubleshooting Temperature Sensors
If the message center is indicating that one of the temperature sensors is faulty, a volt-meter with DC
measuring capabilities can be used to help determine the issue.
Measuring across the red and white wires, the meter should read approximately 5 volts DC. If the reading
is 4 volts or less, there is a chance the sensor has shorted out. Disconnect the sensor from the terminal
block and recheck the voltage on the terminal block. Voltage should read 5 volts. If not, a component on
the control board itself has likely failed. If the terminal block reads 5 volts, the sensor has failed.
Temperature Sensor Detail
Red wire to J2-1 +5VDC or "RED"
Black wire to J2-2 "DATA" or "BLK"
White wire to J2-3 COM or "WHT"
Air Filter
A dirty filter can lead to poor system performance. It is suggested to wash filter at least twice per year.
See Routine Maintenance section of this manual for instruction on how to wash the filter.
07/29/2019

Troubleshooting

23 EI915