Honeywell Thermostat Error Code List and Troubleshooting

2 min read

The passage will discuss Honeywell thermostat error code and how to deal with each error. That way, thermostat user can attempt to solve menial error problem on their own.

Sometimes, a thermostat does not work as it is supposed to. This can be caused by several issues. When this happens, an error code may pop up on the display. This code is actually useful when one tries to solve the error.

Honeywell Thermostat Error Code List

Honeywell Thermostat Error Code 90

There are several reasons for that Honeywell thermostat error code to appear on the display. It might be caused by bad connection in the air handler or issue in the module. Another possible reason is faulty wire connections on the circuit board.

This case mostly happens to older thermostat product because the components aged. It does not mean that newer product will not experience such problem, though. That can be factory defect.

It is possible to actually solve this problem on your own. However, homeowner needs to have a basic skill set to do that. To prepare for the fixing, homeowner needs to have the .right equipment and materials. To ensure the problem is handled well, thorough checking must be done first to see which parts that need to be replaced or tightened up.

Honeywell Thermostat Error Code 53

How about error code 53? This particular error is a part of E1 or E error. It shows that the outdoor sensor might fail to work properly. In results, the thermostat unit does not receive information about temperature and humidity of the outdoor environment.

Here are three ways to deal with that situation.

Making sure that the configuration is accurate

Sometimes, the configuration of one’s thermostat does not support it to see the outdoor environment information. Thus, the outdoor sensor must be setup by connecting it to the EIM. Wireless setup function is used for this task.

Replacing batteries

Another trouble shooting for this particular error code is rather similar to Honeywell thermostat error code bAE Lo which is battery replacement. It may happen when outdoor sensor runs out of battery and does not provide adequate function. In this case two new triple-A batteries would solve the issue.

Checking for faults in sensor and wire

The outdoor sensor or wiring that connects it to the thermostat might be faulty or unsecured. Homeowner can work on tightening the connection. Sometimes replacement job must be done as well.

Honeywell Thermostat Error Code E1

Usually, E1 Honeywell thermostat error code will be accompanied by numeral code on the side. Connection problem might be the underlying issue. As an example, code 34 is a warning for low signal. Thus, homeowner needs to check on the wireless connection. Meanwhile, code 29 shows that the thermostat attempts to create connection with incompatible devices.

Honeywell Thermostat Error Code E1

In this Honeywell thermostat error code list, there is also code 33. This particular error might be caused by an error in the return air sensor. To fix or replace this particular part, you need to remove the sensor. Here are the steps to do that.

  1. Press the “Connect” button on EIM.
  2. Continue pressing for ten seconds until the button starts flashing orange light.
  3. Remove the return air sensor immediately.

Honeywell Thermostat Error Code 40

This Honeywell thermostat error code issue is most likely caused by air filter or indoor coil that is clogged by dust. In result, there might be high pressure issue to the thermostat system. In this case, homeowner can conduct cleaning on their own.

However, there are possibilities of more severe issues happening such as poor compressor condition or broken refrigerant. For such cases, qualified help would be more desirable.

Honeywell Thermostat Error Code 11N

In the list of Honeywell thermostat troubleshooting error codes, code 11N is also a common case. There are many reasons for this code to pop up. In this situation, homeowner better relies on professional help than trying to fixing the issues alone.

Honeywell Thermostat Error Code 89

This Honeywell thermostat error code means the thermostat is unable to detect a cooling or heating unit. In this situation, there are several alternative approaches for solution. If the wiring is loose, you can work to tighten it.

There might be faults in wire too, so replacement might be due. Another possible solution if the error is caused by broken outdoor compression would be replacing the unit.