What is a Fall Tune-Up, and Why Do I Need One?

What is a fall tune-up, and why do I need one?

In San Antonio the air conditioning usually gets all the attention. We need it for a much longer period of time, and San Antonio is just about unbearable without central ac.

Don't forget your heating systems.  The heat pump or furnace needs just as much service as the air conditioning.  Every fall a licensed HVAC technician should perform maintenance to ensure everything is operating safely and correctly.  Most HVAC manufacturers require annual maintenance for their warranty to remain in effect.

It's important to get your fall maintenance performed before you would normally start using the heating.  There is usually some dust and debris that builds up on the burner or heat strips, and the first time the heat turns on all the buildup burns off.  This can set the smoke detectors off, and, of course, this will happen at 3 A.M.  You also want to be sure it is operating safely before it is used heavily.


Furnaces have a few more safety considerations than heat pumps.  Furnaces will always product a small amount of Carbon Monoxide.  Furnaces that are not properly maintained will produce excessive Carbon Monoxide.  While performing the fall tune-up we will:

  • Check for gas leaks.  Leaks can develop over time on any gas pipe joint and can develop over the flexible gas connection.  Older flexible gas connections should be replaced if they do not meet the current ANSI Z21.24 standard.  Brass was commonly used before 1996, and the United States Consumer Product Safety Commission views it as a serious hazard since the solder can fail.
  • Check for Carbon Monoxide.  Furnaces vent Carbon Monoxide out of the home as it is produced, but if the vent should fail or become clogged, this deadly gas will go into the home.  Build up on the burners can also increase the amount of Carbon Monoxide produced.
  • Pull and clean the burners and igniter.  Regular cleaning increases the efficiency and reduces the amount of Carbon Monoxide produced.
  • Inspect the heat exchanger.  Over time the heat exchanger can crack.  It is the barrier between the combustion process and the air from your home that is blown across it to pick up the heat.  This barrier is under constant stress.  If a crack develops, the Carbon Monoxide can mix with the air being distributed through your home.
  • Check the condition of the vent pipe.  Over time the vent pipe can become loose or clogged from birds, rodents or people working around it.  Any obstruction or leak can introduce Carbon Monoxide into your home.
  • Check the safety systems of the furnace.  This includes the door switch (the furnace should not operate if the door is removed) and the temperature limit.  The temperature limit will make sure the furnace will not operate if the temperature is too high.
  • Check the gas pressure.
  • Check the calibration of the thermostat.
  • Check the clearance to combustibles.  We will check around the vent pipe to make sure nothing combustible is too close.  We will also make sure combustible materials weren't accidentally stored near the furnace during the spring and summer.
  • Check the temperature split.
  • Replace or clean the filter if needed.
  • Check the blower motor amp draw.
  • Cycle the unit to ensure proper operation.

Heat Pumps:

Heat pumps do not have as many safety concerns, but proper operation is still important.  For heat pumps we will:

  • Check refrigerant pressures.  Without proper pressures of refrigerant the system will not heat efficiently, or it may not be able to heat at all.  Leaks can develop in the evaporator coil, condenser coil, on any of the brazed connections, or rarely in the line set (copper tubing from condenser to air handler).  This is very important if you know there is a leak present.  Heat pumps operate at a higher pressure during heating versus cooling.  The leak will be more severe during heating.
  • Check thermostat calibration.
  • Engage heat strips (the electric supplemental heat) to ensure they come on and burn off any dust or debris that accumilated over the cooling season.
  • Replace or clean the filter if needed.
  • Check the temperature split.
  • Check amp draw on compressor and condensing unit fan motor.
  • Clean the condenser coil if needed.
  • Cycle the unit to ensure proper operation.

Contact us here or call 210-370-7333 to set your appointment for the fall maintenance of your furnace or heat pump.

For more interesting articles on air conditioning click here