Troubleshooting Guide

 

 

 

 

 

Error

Description

Cause of error

Check point & Normal condition

 

code

 

 

 

 

 

 

 

 

 

 

 

 

• Open / Short

Normal resistor : 10K/ at 25°C(77°F) (Unplugged)

 

44

Outdoor air sensor

• Soldered poorly

 

Normal voltage : 2.5Vdc / at 25°C(77°F) (plugged)

 

 

 

• Internal circuit error

 

 

 

 

 

 

 

 

 

 

 

 

• Open / Short

Normal resistor : 5K/ at 25°C(77°F) (Unplugged)

 

45

Condensor pipe sensor

• Soldered poorly

 

Normal voltage : 2.5Vdc / at 25°C(77°F) (plugged)

 

 

 

• Internal circuit error

 

 

 

 

 

 

 

 

 

 

 

 

• Open / Short

Normal resistor : 200K/ at 25°C(77°F) (Unplugged)

 

47

D-Pipe sensor

• Soldered poorly

 

Normal voltage : 4.5Vdc / at 25°C(77°F) (plugged)

 

 

 

• Internal circuit error

 

 

 

 

 

 

 

 

 

 

Check the resistance

Check Point

1.Estimate the resistance of each sensor.(Unplugged)

2.Estimate the voltage of each sensor.(Plugged)

3.If the resistance is 0V or 5Vdc, then sensor is abnormal

- 75 -

Service Manual

Page 75
Image 75
Heat Controller A-MMH36FA-1, B-MMH12FA-1, B-MMC12FA-1, B-MMC09FA-1 Outdoor air sensor, Condensor pipe sensor, Pipe sensor