Fan Limit Switch Troubleshooting

However the typical temperature settings are as follows.

Fan limit switch troubleshooting.

Fan limit switches can be bought at an hvac supply stores or online. Turn off electrical power to the heating system reconnect the fan motor where you previously disconnected it turn on electrical power to the heating system call for heat. Open the access panel and locate the high limit switch. Pull the white button out to put the fan back into auto mode turning on and off under control of the switch and.

Where can you buy a fan limit switch. This opens the safety circuit and prevents the furnace from heating. The blower motor stops working and overheats. Set the building thermostat to call for heat.

If both the blower motor and limit switch test good than other possible problems may be the contactors circuit board or gas valve and possibly the thermostat. If there is a serviceman switch turn it off. And the limit switch should be pulled out. Fan control limit 90 and 130 degrees fahrenheit.

If not shut the power off at the breaker panel. Fan limit switch troubleshooting list before you get started check the air filters in the system. Push the white button in to force the fan to on or manual or always running mode. To test a limit switch you ll want to check continuity to determine what state the switch is in.

The switch s sensor becomes dirty and stops working correctly. If the fan limit switch worked normally continue as follows. If the fan in your furnace runs continuously or turns off and on too frequently you may need to adjust or replace the limit switch. High limit 200 degrees fahrenheit.

Dirty clogged air filters can cause high limit switches to open. The instructions differ depending on whether you have a combination switch or separate high and fan control limit switches as well as on the specific model you have. Some control guides call this summer. Step 1 remove the top access panel on the front of the rheem furnace.