Unit Cools when using unit controls when wall thermo is used it only blows warm air ??

You didn't mention if you checked for 115 volts at the power supply to the air handler. The unit outside has its own power supply. A lot of times the switch that is on the wall doesn't like to work after its been turned off and back on for service, also check the blower door safety switch. If the blower door hasn't been put back in place properly and snugly it will kill power to the whole air handler. Hope this helps. Good luck

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Download this illustration and then using a good multimeter start basic troubleshooting.


All residential window air conditioners have a cooling system made up of four primary components, a compressor, an evaporator fan, a control or switch, capacitor.When the thermostat is calling for a colder room temperature the compressor is energized. It is normally very quiet. The evaporator is always located on the front of the air conditioner. It also has silver fins. Be sure it is clean. Use a foaming type cleaner and rinse with plain water. Because the evaporator is absorbing heat, it is very cold to the touch. The temperature drop causes any humidity in the air to collect on the evaporator - sometimes called sweat. There is a fan inside the air conditioner that circulates the air for the evaporator and condenser coils. The circulating fan and compressor are running simultaneously. The fan motor has two fan blades attached to it on either end. The fan blade on the inside part of the unit continually draws room air over the evaporator coils, which are cold. The fan blade on the outside part of the unit continually draws fresh outside air over the condenser coils, which are warm. Because the evaporator coils are cold, they cause moisture in the room to collect on them, much like a cup of ice water on a warm, humid day. When the amount of moisture increases, it begins to drip down off of the coils into the bottom pan of the air conditioner.
If the compressor fails to start or the fan you may need to replace the capacitor.
You may need a hard start kit.



Thermostat control The thermostat on a window air conditioner works by sensing the air temperature entering the air conditioner. As the air entering the unit reaches the set temperature it will cause the compressor to turn off. The blower may continue to run depending on the selection chosen on the control panel. Digital thermostats work on a similar principle but display a more precise temperature.
Test for continuity with the multimeter between the two terminals . Warm you should read continuity (contacts closed). If not change it.
Selector switches The air conditioner selector switches allow the user to choose the fan speed. The compressor always runs at the same speed regardless of the settings. If low cool is chosen, for example, the fan runs at a slower speed but the compressor still offers the same cooling capacity. There are other switches to control louver operation and other features on some units.

Bad thermostat or temp sensor.

If after reset the A/C cools then the fault seems related to the thermostat or the cut off pressure switch or load cut off.
However is there is no cooling at all the compressor and the gas pressure- check for leak if gas is absent.- must be checked .
If compressor is suspect you must check the estimate and decide whether it seems better to scrap and buy a new one.

unit may be short of gas. will run for a few mins before low pressure switch turns the compressor off. you will need to get an engineer to check gas pressure

Turn thermostat switch to 'cool' setting. It's a 'heat pump' and is in the heat mode.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/craig_3fa289bf857b1a3c

First you have to identify what causes the problem.
To do this you have to:
1) When engine is cold check the level of coolant. If it is low fill it up.
2) Start engine and check if engine reaches regular temperature. If your engine is not heated enough it means your thermostat does not work properly and should be replaced.
3) If engine temperature is normal, then check the temperature of pipes that go to/from heater core. These pipes are located up the fire wall (easier access is from the passenger side). If pipe/pipes are cold (even engine is warm) it means you heater core is plugged and should be flushed. Keep in mind, flushing the whole cooling system is different from flushing heater core.
4) If pipe/pipes are hot/warm, turn off the fan, switch controller to the hot position, wait for 3-4 minutes and turn on the fan. Note if the cold air blows first or warm air blows first but it cools down in 5-10 seconds. If the air blows cold than it is most probably the problem with blend door or blend door actuator.
5) If air blows warm first and then cools down, then while running engine and remaining the transmission in PARKING position, press on the gas pedal until your engine reaches 3,000 RPM. Check if your heater blows warm/hot air. If it does, then your water pump does not work properly and should be replaced. If the air still cold, I would suggest flushing the heater core.

You have a bad board or bad switch. I would say board. You can have service tech check this out. There is only so far you can go without knowledge of Controls ad electricity. Russ

I just got onto a technician who solved the problem for me. What he had me do was:-

1. Pull dowwn the slider and use a pen to press the ACL button.
   That didn't fix it so...
   
2. Take off the slider (the way you would to change the batteries). There is an ABCD slider switch and mine was set to "C". I moved it back to "A" and now it works! I am not sure how it got to "C" though ???
   

The other thing is I had been messing around with the "Manual/Auto" button under the grill on the wall unit. It was set so that the A/C was off. I'm not sure if that is significant.

Hope that helps.

Cheers,
Garry Rogers (ausgaz)

You have either a faulty thermostat, dirty condenser and evaporator or a faulty run capacitor. Need to service soon before the compressor is damaged. Sea Breeze