 First the basics.
If the breaker crackles and pops when you try to reset it you should just leave it off and call immediately for service.
If it stopped working and then mysteriously started working again it will probably happen again so let us check it out anyway.
If the unit is leaking water it probably will not fix itself with a cup of bleach as that is only recommended for maintenance on units with plastic drain pans.
Air Conditioners in Texas run about 9 months a year and like your car it should be serviced twice a year to maintain efficiency and life expectancy.
 My air conditioner is not running, what could the problem be?
Indoor unit:
Not running at all
- The indoor breaker has tripped
- Thermostat not on or temperature is set too high
- Drain line safety switch has tripped
No Air is blowing out the vents but I hear the motor running.
- Evaporator coil is frozen
—Coil is dirty
—Filter is clogged up/replace
—Unit is low on refrigerant/locate and fix leak/add
*our favorite- the plastic bag that the filter came in was sucked into the blower and is limiting airflow.
No air is blowing out the vents and the blower does not appear to be running.
Outdoor unit:
Not running at all
- Ants are stuck in the contactor
- Breaker tripped
- Indoor drain safety switch has tripped
- Thermostat not set to cool or the temperature is not low enough for it to come on
Fan motor is not turning
Compressor is not running (fan running without the audible hum of the compressor)
- Compressor run or start capacitor is defective
- Compressor high or low refrigerant pressure switches are tripped
—High Pressure: outdoor coil is dirty, fan not turning, system overcharged
—Low Pressure: system undercharged, indoor blower not working, to cold outside
- Compressor is overheated and the safety thermal overload has tripped
—Outdoor coil is dirty, high pressure switch
—Fan is not turning
*our favorite - after years of dependable service the electrical terminals became
corroded and have melted together inside the control box.
My gas furnace is not running, what might the problem be?
Most gas furnaces in operation today are no older than the early 90’s and have a circuit
board with a diagnostic LED with the codes listed on the inside of the blower door.
Use this in addition to the simple sequence of operations to determine what is missing
in the sequence and where the problem might be.
Simple troubleshooting by following the sequence of operation
- No sound no LED light
—Breaker is off
—Service switch (light switch) is off
*our favorite - the cable guy turned off the power to the unit when climbing down out of the attic thinking it was a light.
- Combustion fan motor comes on (and stays on)
- After 30 seconds you will hear a click and the hot surface igniter will come on
- Once the igniter is glowing you will hear another click and the gas valve will open
- Gas valve ignites and then a safety flame sensor should detect the flame and keep the
main gas valve open.
- Once the heat exchanger heats up to approximately 150 degrees the indoor blower
motor comes on.
- The temperature on the thermostat is satisfied and gas valve closes and then the
blower turns off a few minutes after.
My Heat Pump is not running in heat what might the problem be?
- Heat Pumps will have similar problems that you would find under the Air
Conditioning section with a few extra notes to mention
- Every 90 minutes or so heat pumps go into defrost to rapidly thaw any ice that may
have formed on the coil. This rapid defrosting is steamy and normal and is often
confused with smoke.
- Lots of ice on the indoor coil indicates that the unit may not be going into defrost
—Defrost temperature sensor failure
—Defrost control board failure.
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