Check this LIST first, before placing a service call.

You may save a service visit!

1. Check breakers at the outdoor unit, at the main breaker panel, and at the indoor unit (see #2):

outdoor disconnect or breaker outdoor disconnect or breaker magnified indoor breaker panel
At the outdoor unit At the main breaker panel
  • If your air conditioning or heating system is not operating, reset any associated breakers. Do this by pushing fully to off position to reset and then back to the on position. Sometimes a breaker can be tripped even though it looks like it's in the "on" position.
  • After resetting the breaker(s), the equipment may take 5 minutes to start due to a protective component known as a time delay relay. This is normal.

indoor unit door2. Check the indoor unit:

  • In some cases, there is a switch that looks like a light switch but is actually a breaker switch that controls the power to the indoor unit. The switch is usually mounted on a 2x4 near the unit. Be sure this switch is in the "on" position. Since it looks like a light switch, it is sometimes turned off by mistake.
  • Check the access door on the furnace to be sure it is secure. The door may not be installed tight enough to engage the door switch. If the door switch is not engaged, the blower will not run. We find that this sometimes occurs when homeowners change their own filters.

3. Check the outdoor unit (for a/c or heat pump concerns):

  • Check to see if the outer coil of the whole unit (condenser) is dirty. Look for cottonwood, grass, leaves, dirt. Be sure to check the side that is against the home. If debris is found, you can wash it out with a water hose. First, turn off the breaker, then using a garden hose with a nozzle tip, spray off the debris starting at the top and working your way down. In some cases, dirt and debris can become impacted in the coil. If this is the case, a professional chemical cleaning may be needed.
  • We can help--call 972.591.0293 to schedule a cleaning visit.

4. Check condition of filters, change them if dirty.

  • Your filter may be located in your indoor equipment (either attic or closet) or it may be located behind a grill in a hallway or other indoor grill.

5. Check for any obstructions in return and supply grilles.

  • Remove any obstructions you may find.

6. Check thermostat:

  • Be sure the lever or mode selection is in the proper position, either "cool" or "heat".
  • Be sure the thermostat temperature is set low enough (for cooling) or high enough (for heating) for the thermostat to recognize the "need" and thereby send the start-up signal to the equipment.

7. For gas furnaces,

  • check to be sure that the gas has been turned on.

Conditions to report when placing a "no cool" service call:

  1. Determine if both components of your air conditioning system are coming on:
    • Identify if indoor section is blowing air through the vents at normal volume
    • Identify if outdoor unit (compressor and outdoor fan) is cycling off and on normally
  2. Check the visible section of low voltage wiring located outside near the condenser for signs of animal damage or damage due to lawn mowers, weed eaters, or mischievous children. Do not touch the wiring. Report your findings.
  3. 3. Report if you changed your filter recently. If possible, keep the dirty filter for the technician to look at as this can help him when performing diagnostics.

Turn your air conditioning system OFF (at the thermostat) when:

  1. Both the indoor and outdoor units appear to be running, but only room-temperature air is blowing out of the vents.
  2. The outdoor unit is running, but little or no air is blowing out of the vents.
  3. You see ice build-up on the air conditioning piping. If this is the case, turn the a/c to the "off" position and turn the fan to the "on" position. This procedure will help thaw the ice which must be melted prior to our technician's arrival.
  4. There is water dripping through light fixtures, through the ceiling, or leaking onto carpet. By turning the system off, the amount of condensate will decrease and eventually stop altogether.
  5. There is loud metal-on-metal grinding.
  6. You smell a burning odor.

To learn more about air conditioning, see the Top 14 Things You Should Know About Your Air Conditioner.

Colony Air Conditioning & Heating is an A+ rated air conditioning and heating company providing fast, certified air conditioner and heater repair service in Frisco TX, Plano TX, McKinney TX, Allen TX, Flower Mound TX, Highland Village TX, Lewisville TX, Coppell TX, Carrollton TX, The Colony TX, Little Elm TX, and North Dallas TX

We accept cash, check, and all major credit cards