Table of Contents
Summary:
Unit displays a E9 error code. This is related to the return air cabinet mixed air temperature sensor. (Sensor T1)
Possible Cause:
- T1 sensor is short or open
- T1 sensor is out of calibration
- T1 sensor is plugged into the wrong location on the board. Sensor plugs in on CN51 on the Main Board.
Troubleshooting:
- OHM the T1 sensor and see if it is shorted to ground. If shorted replace sensor.
- OHM the T1 sensor and see if it is open, if open replace sensor.
- If the sensor is verified and the wiring tests out good, remove the sensor and check the OHM chart against ambient temperature with it removed. You can also drop the sensor in ice to verify is against the chart at 32 ℉. If sensor does not match chart, replace sensor.
- If all the above are correct, then replace the Main Board.
Chart:
Sensor Location
Main Board Plug Connection
WARNING:
Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.