Payne AC not working. 1. Thermostat set 68 to AC w/fan on. 2. Breakers and switch near heater are on. 3. Outside unit has 220v but is not running. 4. Fan in heater/Ac unit is not running 5. Filters are clean. 6. The heater is glowing red in the 2" circle and is very warm I'm concerned that the heater is trying to provide heat even thou I set the thermostat to AC. I turned everything off until I can understand and learm more and what to check. Can anyone offer any help? Thanks Dan

Sounds like there is no control voltage. Either the transformer to reduce the voltage from 110 volts to 24 volts is not producing the 24 volts needed for control voltage, or most furnaces have a small 3 or 5 amp fuse mounted on the main control circuit board that may be blown. Other "outside circumstances" may involve a break in the thermostat wire...more than likely the red wire if you are getting nothing to work. I have seen evidence of "critters" that have chewed through the low voltage thermostat wiring that would keep the thermostat from controlling anything. To check this, go to the furnace and jumper the red & green wire to get the fan running just to isolate if it is a thermostat wiring severred. Good Luck.

By far the most common problem with air conditions is the relay (known as a "contactor") by the air conditioner industry. This allows a low voltage (24 volts) electromagnet to turn on the 220 volt motor for fan and compressor. A replacement will generally cost about 50 to 75 dollars on Amazon.com.


Look for the wires entering the unit, The pair of wires entering the unit will go into a small (4" x 2" x 2") unit (the contactor). Another pair small diameter wires will go into the contactor (those are from the thermostat (or control panel of your furnace blower) and control the electromagnet switch.

The pair of output wires exit the unit and go to the compressor motor and fan.

You can check the output power by
1) Turning off the circuit breaker to the A/C
2) Unplugging the switch (must be a second switch within 3 feet of the A/C) near the house
3) opening up the outside panel on the A/C
4) Set voltage meter probes on the two output wires on the Contactor (make sure voltage meter is set to 220 volt AC range or higher)
5) turn on the outdoor switch
6) turn on the circuit breaker (if no body is near the unit and you can see the voltage meter without touching it)
7 check voltage meter to see that is says 220 volts AC

If not, then the contactor is bad and needs to be replaced.

A professional can usually do it for $200 including service call. I highly recommend calling a professional if you feel uncomfortable in any way about working with 220 volt systems. This voltage will kill you if you make a mistake!

-Mark

Could be under sized unit or fan relay on unit.

I assume it runs and this is from that stance. If it doesn't the motor has to be checked and the power coming in. In fact the dryer can run and still not have the correct power to opperate the heater.

Assuming you have a volt meter and know how to use it properly.

These are the steps that the power and machine have to take to operate properly

A. If the dryer has all of these things it has to be heating and an air flow problem (kinked or dirty dryer duck, motor fan clogged with lint, vent flapper not opening...) is suspect.

B. ELECTRICAL
1. power is correct (USA 220V across line and 115v to ground/neut) 2 hot lines with potential between them and a neutral and possible a ground
2 Door switch is closed
3 Timer switch closes and ready s power to heating element through centrifugal switch in the motor circuit after the motor is running.
4 the heating element is assumed to be good and have 220v at this point. Checking for voltage at the element will assure all before are ok and at least allowing the heater to work.
5 the heating element is controlled by 1 or more thermostats and a safety thermostat. If either of these switches do not close when the dryer is "cool" they are bad. NOTE some dryers could ahve 3 wire thermostats. These can read closed on one set and open on the other. And this is how they should be if good. But tracing the wire diagram will tell which set is closed and when.
6 if you have power, the timer contacts to the motor and the heater (separate circuits usually)are "closed", the motor runs, the cent switch "closes", the temperature operating thermostats are closed, and the heating element is good you have to have heat.

1 Check for 220V power into the dryer. If not check breakers and turn off and on several time pushing them firmly. If this is ok and 220V present step 1 is done.



2 This assumes the motor will run

Hi, the wiring terminations are near consistent with a 24 volt ac furnace and I will tell you how a 24 volt stat is terminated. RC= 24 volts jumped to RH for red wire only. This would be for a central system with air and heat. W=white for heat, G= Green for Fan, and Y = yellow for cooling. I do believe it is wired correctly for your application. Please verify your units model and serial number and give me a clue as to what is taking place, and did you change the thermostat or make a part change?
Sincerely,
Shastalaker7
A/C, & Heating Contractor.

lower temp setting lower then outside temp should work

The first thing to check is your breaker box. There should be one double breaker for the air handler unit, that's the inside unit, and one double breaker for the compressor, that's the outside unit. Check both breakers. If you're not sure if they've be thrown, click them toward the outside of the breaker box (off position) and then click them toward the inside of the breaker box (on position). If the breakers are on and you still are not getting any A/C take a look at your compressor, (outside unit). If the fan is running at least you're getting power. However, your compressor down inside the unit may not be getting power or it may need to be replaced. The compressor has a start-up cap. If this cap goes bad or the wires from this cap fry or corrode away, this will also keep the compressor from starting but the fan will still run. If the fan is not running it could be caused by a faulty relay inside the compressor cabinet. This relay is supposed to open and close based on a low voltage signal from the thermostat. I believe it's roughly 24 volts. This relay switches on and off the 240 volts for the compressor and the compressor fan. Often this relay goes bad or the wires leading up to it fry. If you?re going to work on the unit yourself make sure all power is shut off. There should be a shutoff switch on the outside wall near the compressor. I?d also shut the breakers off.

by the outside unit, you will have a shutoff. pull out the shutoff, and unscrew the cover. 2 cylinder like fuses are inside. It is likely that one or both are bad. When you turn on the AC and the outside fan does not turn on... this is likely this is the solution.

open the service panel to check for control voltage of 24volts when tstat calling, The contactor should be pulled in, if contactor is down,and contacts appear to be clean, and the unit is still not running, it is a bad compressor. to test this unplug the black wire from the compressoror at contactor,w/ power off! Turn on power if fan works normally it's a bad compressor. However if you see a swollen split cap(5 wires to a soup can looking w/ the terminal C,F,and Comp), switch it first and start at square one.
You also need to consider the high pressure switch if its cycling on off on off.

Blank screen sounds like a fried thermosat. Abrupt outages can affect certain types of thermostats. Make a jumper wire and jump across R and G. See if you get any action from anywhere. If a fan or compressor kicks in you know you have a burned out thermosat...