I have a amana ptac through the wall unit. the evaporator keeps freezing up on me. what is causing this

Question edited for a lot more clarity.

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Probably this one. Talk to your installer.

https://www.amana-ptac.com/products/ptac/hec154j

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Question edited for clarity and toss in some CAPS.

You can get wired or wireless.

https://www.amana-ptac.com/products/ptac

Fitting

https://www.google.com/search?q=amana+ptac+connect+to+wall+thermostat

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You said in another post that the error was c7. That means evaporator freeze. Too cold. That could be lack of air flow, bad sensor, ice on the coils.

it's known as the split. Room air going into the unit should be 10 to 12 degrees cooler coming out. Unit size, area to be cooled, insulation value and local weather are considered. If the split is close to the numbers the unit is doing all it can. If it's low on freon the evaporation coils will freeze and ice over.

If you are not going to run the unit put a large bag over the out door section. The unit will be just fine.

If you need further help, reach me via phone at https://www.6ya.com/expert/thomas_092728000e6acb79

I don't see this error code in the manual. I do see nP as an error code for Window Switch lockout. I just had this happen to me and they had me reset the control board.

Remove case, flick master switch to OFF for 10 seconds. Press Heat/Cool same time turn switch back on HOLD until off light comes on.

You should be fixed. Just had to do this for my unit. I was playing around with the settings and turned on the window switch option by accident.

I think your PTAC is under charge, if the air filter is clean and the evaporator is also clean together with the blower. Check the freon charge and refill if suction pressure is below 50psi and discharge is below 190 psi.

Yes, the client is keeping the unit on too cold. In my opinion, this design is wrong, wrong, wrong. When a user is not cool enough they turn the unit colder, and cause this icing up.
The best design keeps the evaporator coils above freezing at all times, automatically. Users have no idea and really cannot be expected to understand this issue.

Cars did the same thing (even Mercedes), and it is just nuts. If I was in your position, I would seek to have amana make a modification kit that would sense the evaporator temperature and interrupt the compressor until the temperature rises enough to keep icing under control. Under that scenario, max is max, period, but the unit will put out cold at all times, rather than icing up.

I have seen this happen many times and if you cannot relocate the bulb of the thermostat to keep it form short cycling, I have mounted a wall thermostat and disconnected the thermostat in the PTAC and wired it in to the wall stat. You may have to install a wall stat in the center of the room away from the bar.

see if you can find a new board the power failure fried it