High Limit Switch Furnace Troubleshooting

Next check the filter.

High limit switch furnace troubleshooting.

The limit switch is a safety switch that monitors t. Flip the switch on the side of your furnace and flip the breaker off and on again before you even think about replacing any parts. The flames would raise the temperature inside the unit and have no place to go getting hotter and hotter. Clogged furnace filter a dirty or clogged filter blocks the air flow into the furnace which may raise the inside temperature of the unit.

It also can shut down the furnace burners it if gets too hot inside the furnace. For example if the blower motor stopped running then no air would move through the unit. High limit switch a high limit control switch will turn off the gas to a furnace if the temperature becomes too high. Limit switches turn off the burner and turn on the circulating fan if there is a high temperature condition in the furnace.

When the temperature gets too high the high limit switch turns off the gas to the furnace. During your tune up not only will we inspect your limit switch but we will also take care of airflow issues with your system that can cause your limit switch to break down. One way to keep your limit switch in good shape is to schedule a furnace tune up every year with jerry kelly. In this episode of repair and replace vance shows how to replace the high limit switch in a gas furnace.

Fan control limit switch. How to check limit switches using your voltmeter. If the furnace failure code indicates an open limit or open high temperature switch or open rollout switch it is probable that the furnace has overheated. The high temperature limit switch senses the temperature of a furnace and tells the blower fan to turn on and off at the appropriate times.

As a working example we examine the honeywell combination fan and limit control type l4064b.