Air Quality

Replace my furnace when replacing my AC?


For the homeowner whose ready to improve efficiency and lower utility bills or if your AC system has been diagnosed with a coil leak, the first question that I’m usually asked is “Do I need to replace both the AC & the Furnace?” Answer is … it depends.

Most people associate the furnace as only the heating component of the system, but the furnace also contains the wheel and motor which the moves the air through the duct work aka – the blower.

In South Texas, the furnace is not used as often as in other climates for the heating function, but the blower is used every time the system is running, heating or cooling.

Technically, the components that need to match are the coil and the condenser. They share the refrigerant. The gas furnace does not use the refrigerant and is only responsible for the circulation of the air and heating the air, so an AC & coil can be replaced and the furnace remain.

When it becomes necessary to change out the AC due to evaporator or condenser coil leaks, the furnace and blower should be changed out as well if it is over 8 years old.

The new condensers are higher efficiency. Pairing a new compressor with an old blower will compromise the energy efficiency the condenser would otherwise be able to achieve with a comparably aged matching furnace and air handler.

Frequently older blower motors can’t keep up with a new high efficiency compressor for long, so unless you want to get into the repair and “parts” replacement game, it’s best to replace all components at the same time and take the 10 year equipment warranty and higher efficiency ratings that are achieved with components of the same age. Your energy provider like CPS also will not offer rebates unless the system pairings are matched and a certificate of energy efficiency is submitted.

Call for a free video or on-site system replacement consultation. (210) 944-TPRO