How to Troubleshoot a Honeywell Timer ST9141A1002

A Honeywell electronic fan timer controls the combustion blower and circulating fan on a gas home heater.

Fan Timer is Not Working

A Honeywell electronic fan timer helps keep your home at a comfortable temperature.A Honeywell electronic fan timer helps keep your home at a comfortable temperature.
The timer is connected to the thermostat, which controls demands for heat, cooling and air circulation. It also controls the air cleaner and humidifier functions for the heater. The electronic fan timer should be installed by a qualified electrician. However, you can troubleshoot a few problems yourself to determine if you need the services of an electrician.

Step 1

Check to see if the LED display on the timer is lit up. If the display is dark, check that the main power supply is 120 volts of alternating current at 60 hertz. Contact an electrician to upgrade the power supply if it is less than 120 volts of alternating current at 60 hertz.

Step 2

Check the wiring diagram for the location of the fuse and line 1 that goes to the power supply. Find the fuse and line 1 on the unit. Locate standard terminal 1 on the wiring diagram and on the unit. Visually trace the voltage connection from line 1 to make sure it connects to the standard terminal 1 on the heater.

Step 3

Check the wiring diagram and then the unit for the location of line 2 and the neutral standard terminal 3 on the heater. Visually trace the voltage connection from line 2 to make sure it connects to the neutral standard terminal 3 on the heater.

Step 4

Call an electrician if the line 1 and 2 connections are not set up correctly.

Thermostat Does Not Work

Step 1

If the power supply is at the correct voltage and is hooked up correctly, determine the correct wiring from the thermostat to the cooling contactor by looking at the electronic fan timer wiring diagram.

Step 2

Trace the line voltage connections from the thermostat connector W to the cooler contactor connector W. Trace the line voltage connections from the thermostat connector Y to the cooler contactor connector Y. Trace the line voltage connections from the thermostat connector G to the cooler contactor connector G. Trace the line voltage connections from the thermostat connector R to the cooler contactor connector R.

Step 3

Call an electrician if the line voltage connections from the thermostat to the cooling contactor are not wired correctly.

Heat Delay Off is Not Correct

Step 1

Locate the DIP switches to set the heat delay off for the heater. Decide how long of a delay you desire before the heat goes off.

Step 2

Push the switches with your finger so that the switches both show a white box on top and a black box on the bottom if you desire a heat delay off of 60 seconds.

Step 3

Set the left switch with the black box on the bottom and the right switch with the black box on the top for a heat delay off of 120 seconds.

Step 4

Set the left switch with the black box on the bottom and the right switch with the black box also on the bottom if you desire a heat delay off of 140 seconds.

Step 5

Set the left switch with the black box on the top and the right switch with the black box on the bottom for a heat delay off of 180 seconds.

Things You Will Need

  • Owner's manual
  • Wiring diagram

About the Author

Mary McNally has been writing and editing for over 13 years, including publications at Cornell University Press, Larson Publications and College Athletic Magazines. McNally also wrote and edited career and computer materials for Stanford University and Ithaca College. She holds a master's degree in career development from John F. Kennedy University and a bachelor's degree from Cornell University in counseling.