Troubleshooting Atwood Furnace Error Codes

Do you know the best time to troubleshoot your Atwood furnace? When it’s giving you error codes*, of course. Troubleshooting an Atwood furnace is much easier if you know exactly what error code you are dealing with. The different error codes often indicate a problem with the sensors or controls, not the heat exchanger. Knowing what could be causing that pesky red light and its corresponding error code will help you diagnose and fix it faster than ever before. Red light, green light, yellow light… If your heat doesn’t seem to want to turn on or comes on, but won’t shut off, there could be one of many reasons why. But thankfully, we have troubleshooting tips for each of these common problems as well as their respective Atwood furnace error codes.

Error Code -1

The error code -1 means the furnace does not see any communications from the thermostat. This can be caused by an incorrectly wired thermostat, incorrect or incorrect settings on the thermostat, or a thermostat that is not communicating with the furnace. If you have verified all wiring is correct, take a look at your thermostat’s owner’s manual to see if there are special settings you should be using.

Error Code 14

An error code 14 means that the sensor that detects the pressure inside the furnace to determine if there is a blockage is not reading properly, either because the sensor is clogged or because the sensor is bad. In some cases, the sensor will get clogged with minerals in the water. In others, it is poor quality, or the wrong type for the furnace. To clean the sensor, you can use a shop-vac, or blow compressed air through the sensor to clean it out. If the sensor is bad, you can either replace the sensor or clean it and put it back in, depending on how accessible it is.

Error Code 19

The error code 19 means that the thermostat is not communicating with the furnace or the furnace is not communicating with the thermostat. To rule out any wiring issues, turn the furnace off, unplug the thermostat, and plug it back in. If the furnace still does not communicate with the thermostat, check the settings on the thermostat and make sure they are correct. If everything is correct, then there may be a bad connection between the thermostat and the furnace. Before you call a technician, make sure the thermostat and furnace are plugged into the same breaker. If they are, check to see if the wires are touching or if there is some sort of short.

Error Code 28

An error code 28 means that the flame sensor is either bad or incorrectly installed. This can happen if the sensor gets moved or loses its seal. If you have verified the sensor is installed correctly, then you might need a new sensor. If it is bad, you can clean it with compressed air or replace it.

Error Code 31

An error code 31 means that the furnace does not see a call for heat from the thermostat. This can be caused by an incorrectly wired thermostat, an incorrectly set thermostat, or a thermostat that is not communicating with the furnace. To troubleshoot, turn the furnace off, unplug the thermostat, and plug it back in. If the furnace still does not see a call for heat, check the settings on the thermostat and make sure they are correct. If everything is correct, then there may be a bad connection between the thermostat and the furnace. Before you call a technician, make sure the thermostat and furnace are plugged into the same breaker. If they are, check to see if the wires are touching or if there is some sort of short.

Error Code 38

An error code 38 means that the flame sensor is not reading correctly. This can be caused by an incorrectly installed flame sensor, a sensor that is clogged with minerals, or a sensor that is bad. If the sensor is installed incorrectly or is dirty, you can clean it with compressed air or replace it. If the sensor is bad, you can either replace the sensor or clean it and put it back in, depending on how accessible it is.

Error Code 40

An error code 40 means that the furnace does not see a call for cool air from the thermostat. This can be caused by an incorrectly wired thermostat, an incorrectly set thermostat, or a thermostat that is not communicating with the furnace. To troubleshoot, turn the furnace off, unplug the thermostat, and plug it back in. If the furnace still does not see a call for cool air, check the settings on the thermostat and make sure they are correct. If everything is correct, then there may be a bad connection between the thermostat and the furnace. Before you call a technician, make sure the thermostat and furnace are plugged into the same breaker. If they are, check to see if the wires are touching or if there is some sort of short.

Conclusion

When an Atwood furnace is giving you error codes, you know it’s time for troubleshooting. The best way to know what error code you are dealing with is to look it up in your owner’s manual and then troubleshoot accordingly. Some errors can be fixed with a simple cleaning, while others might require a professional. Knowing what could be causing that pesky red light and its corresponding error code will help you diagnose and fix it faster than ever before.