How to Troubleshoot & Reset Your Amana PTAC Unit

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One of the largest producers of PTACs (Packaged Terminal Air Conditioners) is Amana, known for producing some of the most reliable PTAC units around. However, like any other appliance, these units sometimes develop issues.

Depending on what’s wrong with an Amana PTAC unit, the fastest way to solve the problem is to reset the system. Keep reading for a step-by-step to troubleshooting and resetting an Amana PTAC device. 

How to Troubleshoot Your Amana PTAC Unit

Thanks to clever innovation, you can troubleshoot your Amana PTAC unit without any tools or technical skills. These air conditioning units come with a self-diagnosis feature that you can activate at any time. 

When you put your PTAC unit in diagnostic mode, it scans for errors and displays a unique code. Using the error code as a pointer, you can determine if a manual reset will get your PTAC unit working smoothly. 

How To Do a Self-Diagnostic Test on Your Amana PTAC

Follow these step-by-step directions to run a diagnostic test on your Amana PTAC unit:

  • Locate the “down” and “up” arrow buttons on the unit.
  • Hold down both buttons simultaneously. 
  • While holding both buttons, double-tap the “Cool” button on your PTAC unit. 
  • Wait a few seconds for the display to change. 

If you follow the method above correctly, your air conditioner unit should be in self-diagnostic mode. To make sure, spot a red dot flashing in the corner of the screen. 

Typically, the PTAC’s display screen has numbers indicating the temperature of the room. While in diagnostic mode, dashes (- -) will replace these numbers. You may also notice a green light in the bottom left corner of your device’s touchpad.

Give the device a few minutes to run a diagnostic test. When the test is complete, an error code will take the place of the dashes. 

If the dashes are still in place, it means the system is unable to detect the error. Therefore, the system may not work smoothly even if you reset the Amana PTAC unit. It may be best to call in an air conditioner repair technician.

Troubleshooting Your Amana PTAC Unit: Error Codes and How to Fix Them

After troubleshooting your Amana air conditioner using the self-diagnostic feature, the device will display an error code. We can group these codes into four categories:

System Modes

System modes point to errors in the operating framework of your Amana PTAC unit. Typically, you can fix them by changing some settings or the location of the PTAC unit.


The error code “On” indicates the unit works in tandem with a wired thermostat instead of a wireless system. Simply change the configuration settings to the proper mode to alleviate this error.


“FP” means your Amana PTAC unit is now working in Freeze Protection. The Freeze Protection kicks in when the temperature of the environment is below 40℉.  

This kicks in to prevent components from freezing and suffering damage. To exit Freeze Protection, move the unit to an area where the temperature is over 43℉.

oP / nP 

These error codes occur when your Amana air conditioner detects an open window or a door. The system will stop working to prevent energy wastage. 

You don’t need to reset your Amana PTAC device. Simply close the open window or door. 


The “HP” error code is an indication that the Amana PTAC is in danger of overheating. In this situation, the device goes into Heat Sentinel mode to prevent damage to essential parts. 


This error code means the device’s service board has the wrong configuration. The best way to fix the “Eo” error code on your Amana PTAC unit is to reset the system manually. The device will go back to its default configuration settings and should work smoothly.


The error code “EH” indicates the PTAC unit is now under Emergency Hydronic functions. It means the compressor isn’t working, and the EHH switch is in the “off” position.


“LS” means Load Shedding. It means the electric heat, as well as the compressor, is in the off position. To exit Load Shedding mode, turn on the LS switch. 

Refrigeration Errors

Refrigeration errors indicate there is a fault with your PTAC’s refrigeration or cooling system. If your device shows any of the error codes below, you may need to call in a refrigerator repair expert,

C1, C3, and C4

Any of these codes are a signal that your device’s indoor coils are starting to freeze. Applying a manual reset to this situation won’t get your Amana PTAC device working smoothly.

Start by cleaning out the air filter and checking for defects in the blowers or fans. Also, check whether refrigerant levels are at an optimum. 


The “C6” error code indicates an overall poor system performance. It means multiple parts of your PTAC air conditioner are in bad condition. Check the state of the compressor, blower motor, and other electrical components. 


This error code is an extension of the freeze warning for the indoor coils. “C7” signifies the unit is automatically locking the controls for safety reasons.

Airflow Alerts

The operation of the average air conditioner works due to principles of airflow. If you encounter any of the following error codes while troubleshooting your PTAC unit, you’re dealing with airflow issues.


Error code “L6” means that outgoing air is too hot for the Amana device to work normally. The best fix to this error code is making sure the air filters are clean. 


This error code is a sign of a more significant issue with the condenser fans. It means the outdoor thermistor (red) is getting too hot for the system to work correctly. If the fan is working properly, you can fix this problem by cleaning the condenser coils. 


“C2” means the device is recirculating the air present inside the room. When this happens, the device will be unable to cool the space adequately. You may also have air integrity issues. 

The best way to fix a “C2” error code is by checking the seal around the unit. You can also try closing the vent door and cleaning the filter. 


C5 means the outdoor coils are too hot. Remove any object blocking the flow of air into your Amana PTAC device.


This category of error codes means a particular component has completely stopped working. The only way to fix these error codes is by replacing the damaged part. 


“F1” is indicative of a double failure. It may be that the indoor thermistor (black) is getting readings outside the normal range and that the wireless thermostat is no longer working. 


With this error code, the indoor thermistor (black) is working fine. However, the wireless thermostat is no longer working. You’ll need to call in an air conditioning repair expert to fix it. 


The thermostat is working optimally, but the indoor thermistor (black) is working outside the normal range. 


The indoor thermistor (red) is no longer working correctly. The only solution is to replace it.


It indicates an outright failure of the Indoor Discharge Thermistor (yellow). Most likely, the thermistor is above or below the standard operating tolerance.


This error code means the batteries in the PTAC’s remote are low. Simply replace them to resume regular operation.


High voltage can damage your Amana PTAC device. An error code “H1” means the incoming voltage is too high. 


The error code “Br” means your Amana PTAC unit has triggered Brown Out Protection. This protective feature kicks in due to low incoming voltage. 

Troubleshooting Your Amana PTAC Manually

The error codes above don’t cover every possible malfunction that your Amana PTAC device may develop. Other faults to consider include:

Unit Not Powering On

Check that the Amana PTAC unit connects appropriately to a power source. Check for bad wiring and breakage in the connection.

Zero Heat

Heating issues may be due to a bad thermostat or low voltage. If the internal overload control is in the on position, your PTAC unit won’t heat the room properly.

Cooling Problems

Check the thermostat and ensure it’s working properly. Also, you want to make sure the refrigerant level isn’t low.

How to Reset an Amana PTAC Unit

It’s possible to fix some of the issues above with a simple manual reset. There is no one rest button, but it is still a straightforward process. Here’s a step-by-step to resetting your PTAC unit manually:

  • Check that the unit is on 
  • Lift the forward-facing plastic covering by lifting it and pulling it in your direction.
  • Turn the master switch to the “off” position. It’s usually under the control panel.
  • Locate the “cool” and “heat” buttons 
  • Press down on both buttons simultaneously 
  • While holding both buttons, turn the master switch to the “on” position. 
  • A red light beside the “off” button means you have successfully reset your Amana PTAC unit.

Final Words

Thanks to the self-diagnostic feature, it’s easy to troubleshoot and diagnose a faulty Amana PTAC device. 
Depending on the fault, a simple manual reset may help get your unit working properly again. And if you find yourself in need of a new or refurbished Amana PTAC, we’d be happy to help you find the right one for you here at PTAC4Less!