Is it Dangerous or Wrong to Switch Back and Forth From Heat to AC?

Yes, we are still in winter, but we’ve seen a few days with warm temperatures, only to fall right back down into the 20s. For many of us, we can simply turn off the system on the warmer days and be ok. But for a lot of us, working or sleeping in a warm house is hard to do. We’re tempted to flick on the AC for the day. But what about when the temps get cold again? Is it bad to keep jumping back and forth from heat to AC back to heat in order to stay comfortable in our home? Is that going to damage our systems? From now until well into Spring, you may find it difficult to regulate the temperature in your home. Especially when it’s warm during the day and cold at night. 

In general, switching back and forth between heating and cooling modes won’t cause any problems. However, sometimes switching back and forth can cause your system to shut off. You could potentially “short-cycle” the air conditioner which could blow a fuse. When a compressor locks up during high pressure start-ups, it will draw a very high amp rate which can cause a breaker or fuse to blow. Some units have built-in timers while some digital thermostats have built-in time delays to prevent this from happening. 

The Right Way to Do It

If you need to switch from heat to AC (or vice versa), here are the steps to remember: 

• Let your unit complete its current cycle by waiting until it switches itself off- thermostat set to AUTO, not ON. 
• When the cycle is complete, turn the thermostat to OFF and wait five minutes. 
• Then change it from AC to heat (or vice versa) and turn it back on.
• Easy does it! When switching between heating and cooling, don’t make drastic changes all at once, instead raise or lower the temperature a few degrees, then a few degrees more once it reaches that setting until you reach the perfect temp.

Using these steps is the most efficient way to get where you want to be while preventing your system from overworking. That five minute waiting period gives the refrigerant a chance to equalize and return to its starting pressure. If you turn it back on right away, the pressure is too high, which might cause the compressor to lock up and can lead to a blown fuse or tripped breaker.

A blown fuse is something that you may be able to handle yourself, however, should your system shut down, you’ll need to contact your professional HVAC contractors at Xcalibur in Birmingham, AL. The problem may be more complex, although resolvable! 

If you follow the advice of letting the thermostat sit in the OFF position for 5 minutes before switching to the opposite setting, you shouldn’t have any issues going from heat to AC and back to heat. 

Just like we always say, we recommend regular HVAC maintenance to help prolong the life of your equipment. Tune ups can prevent minor issues from becoming major ones. If you’re having a hard time regulating the comfort of your home even when outdoor temperatures aren’t fluctuating, it’s time to give us a call. We will gladly make the necessary repairs or replace your unit with a new air conditioner or furnace if that’s what is needed. 

We want you to be comfortable in your home, so if that means switching back and forth between heating and cooling, go for it! Just make sure to do it the right way (as discussed above) in order to keep your unit functioning correctly. 

If any issues arise, whether you’re switching back and forth or not, contact us! As your trusted HVAC contractors in Birmingham, AL, we’re ready and able to help with your heating and cooling needs.

Published: February 2nd, 2021