Auto-Zone Control Systems Auto-Zone Plus Systems Installation & Operation (Version 03A) - Manual (Page 203)

Auto-Zone Plus Section 4
Start-Up and Troubleshooting 4-53
Zone Sensor reading incorrectly
• Is the sensor near a source of heat or a cold draft? Location is a common problem.
The sensor should be mounted on an inside wall away from heat sources and in a
location with adequate room air circulation.
• Is the resistance reading correct? Check with the Temperature/Resistance Chart in
this section.
• Is wiring correct? Check for errors.
Check the Room sensor
• To meter the Room sensor:
Unplug the two position room sensor terminal block. Using your meter, check the
resistance of the unplugged terminal block. Use the supplied
Temperature/Resistance Chart to see if the sensor is within a reasonable range.
Readings which are much too high or too low generally, indicate wiring problems.
• To meter the Slide Adjust (optional):
Unplug the four position AUX terminal block. Use your ohmmeter to check the
resistance between the GND wire on the two position room sensor terminal block and
the AUX1 terminal on the unplugged terminal block.
The resistance for various positions of the slider on the sensor should be as follows:
Full UP position 15K Ω (± 500 Ω)
MID position 12.5K Ω (± 500 Ω)
Full DN position 10K Ω (± 500 Ω)