How Do Furnaces and Air Conditioners Work Together?

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Did you know that your air conditioner and furnace need each other to work properly? More than just sharing ductwork, these two systems cooperate to create the properly balanced temperatures and humidity that you enjoy inside your home year-round.

Understanding this relationship can make it easier to see problems on either system. It can also help to know why technicians may need to take into account both the furnace and air conditioning unit when doing repairs.


Furnace Heating Basics

No matter which type of furnace you own to produce heat–gas, electric, or oil–they work basically the same way to heat your home. When your thermostat sends the message that your home’s temperature is too low for your liking, it starts up a series of events to get that temperature back up. 

The first signal is sent to your furnace, found inside your home, to start up the heating process. The second signal is sent to the motor that starts up your HVAC fan, found outside your home, to get that warm air pumped through the house. Once everything is up to your liking, the signal goes out to shut down both systems until further notice. 


How an A/C Works

So what happens when the opposite is needed? If you have central air you’ll notice a lot of work being done by the air conditioner located on an outside wall of your home. But what you may not notice as much is the furnace’s part in cooling your home

When your thermostat sends the cooling signal to your units, it’s telling the outdoor unit and the indoor coil, found on top of the furnace, to start up and get to work. Using electricity, the air conditioner unit pumps refrigerant that gathers heat and moisture, blowing it over the indoor coil. This process allows the warm air to transfer to the coil, leaving the cooled air to circulate your home. 


HVAC Repairs for A/C and Furnace

Because both your heating and cooling systems depend on one another to operate, solutions to problems with either system may not be where you first expect them. If either unit is having problems, don’t be surprised if your technician needs to see both units before making a complete diagnosis. Or if a repair needs to be made on the furnace in order to fix your air conditioning problem, or vice versa. 

It’s also important to think about both units in terms of efficiency and maintenance. Simply focusing on one unit during the season may have its drawbacks if you are ignoring the other unit for a prolonged amount of time. This can be something we see in areas like ours quite a bit. Because seasons are generally hotter, many people don’t think they need to pay as much attention to their furnace, but the truth is that without the furnace, their A/C wouldn’t be cooling much at all. If you have any problems or questions about your HVAC unit, furnace, central air or otherwise, please give us a call. We are here to help day or night, and weekends too.