Can We Use AC To Warm The Room?

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We all know AC (Air Conditioning) to be an ideal appliance that can keep our rooms cool even during the hottest season of the year. AC can save us from extreme heat in summer, but can it save us from extreme cold in winter also? Can we really use AC to warm a room?

We can use AC to warm a room as long as the manufacturer of the AC designed it to have heat mode. Almost all modern air conditioners have heat mode in addition to cool mode.

When you switch an AC to heat mode, it won’t convert electric energy directly to heat energy. Instead, it will use the electric energy to move outdoor heat into the room until the room’s temperature rises to the desired temperature. Kindly read on to see more pieces of information about the heat mode on AC.

Can We Use AC To Warm The Room?

We can use AC with heat mode to warm a room. The heat mode on AC works with a principle different from that of space heaters. When you activate the heat mode of an AC, a reversing valve within the AC will reverse the entire operation of the AC. Here is what an AC with a heat option looks like.

The cold evaporator coils will start to function as hot condenser coils and vice versa. As a result of this interchange, the indoor unit will begin to expel cold air and draw warm air into the room. Once the room’s temperature reaches the temperature you set, the indoor unit will stop its processes. The indoor unit will resume its processes as soon as the temperature falls below what you have set.

Whenever an AC is warming a room, it will still remove excess humidity from the room’s air. An AC is more economical for heating since it uses less energy when compared to space heaters. Unlike heaters, AC does not require energy to generate heat. Instead, it requires energy to operate the compressor and the fans, which will then transfer outdoor heat into the room.

How Do You Use Heat Mode On AC?

If you own an AC with heat mode, kindly follow the instructions here to activate the heat mode. Start by pressing the “mode” button on the remote control. Keep pressing the button until the mode setting advances to “heat.” Most air conditioners have five mode settings, which include auto, cool, dry, heat, and fan.

Once you have successfully changed the mode to “heat,” you should press the “temp ↑” or “temp ↓” button to increase or decrease the heat mode temperature. Some remotes use “+” and “-” for temperature adjustment, so if yours doesn’t have “temp ↑ ”or “temp ↓” buttons, you should adjust the temperature with “+” and “-” buttons. Finally, you should press the power button to activate the heat mode.

If you want to warm your room quickly without setting the temperature too high, we recommend that you increase the fan speed. High fan speed promotes heat circulation in the room. Kindly note that the fan may not work as soon as you activate the heat mode. Once the indoor unit becomes warm enough within a few minutes, the fan will start working.

In case the fan doesn’t work for more than 5 minutes, you should watch out for an indicator light that stays on or blinks. An indicator light that stays on or blinks while the fan isn’t working means that the AC is running a defrost cycle. A defrost cycle clears ice or snow deposited on the outdoor unit before heating up the room. A defrost cycle might run for about 15 minutes, so be patient if you are activating the heat mode on a very cold day.

Is It Bad To Switch From AC To Heat?

It isn’t bad to switch from AC to heat, but you need to be careful while doing so. It’s wrong to switch from AC to heat while the AC cycle is yet to be completed. The compressor may get locked up if suddenly switched from AC to heat before the unit completes the current cycle.

Even if the unit has completed the AC cycle, you still have to wait for about 5 min before you switch to heat. The waiting period allows the compressor to return to the default pressure. The pressure inside the compressor can become too high if you switch from AC to heat without waiting.

A sudden switch from AC to DC will stress the entire system and not just the compressor. Such stress may increase energy bills and even blow a fuse. If you own a modern AC with digital thermostats, the thermostat will hinder you from switching from AC to DC too suddenly, so it’s almost impossible to stress the system.

However, you still have to be cautious because the thermostat may someday fail to work. Also, you should raise the temperature gradually when switching to heat. You can keep on raising the temperature by a few degrees every 10 minutes until it reaches the temperature you desire. This will allow your system to work efficiently and last longer.

When Should I Switch From AC To Heat?

Sometimes, it can be confusing to know the right time to switch from AC to heat, especially if you live in a region where the temperature fluctuates between extreme values during the day. You are free to switch from AC to heat when your room becomes too cold and humid in the winter. For most people, a temperature below 17°C is cold enough to make them feel uncomfortable. Although the indoor temperature is the major factor for determining the right time to switch to heat, it would be best if you consider the outdoor weather also.

You should avoid heating your room with AC when the outdoor temperature falls below 15°C. If you use your air conditioner when the outdoor temperature is below 15°C, the compressor will be very prone to seizure since the lubricant it requires for a smooth operation will become thick. 

You may be tempted to warm your room with AC immediately after a big snowstorm, but we advise you to inspect the outdoor unit before switching to heat. You can switch to heat if you notice little snow around the outdoor unit, but if the unit is completely covered with snow, you shouldn’t switch it on. Air conditioners can remove a little quantity of snow by running a defrost cycle, but the defrost cycle can’t deal with large snow quantities. 

If you operate the air conditioner while it is completely covered with snow or ice, the AC will have to overwork, and this can lead to damage. The compressor, in particular, will get overheated as it overwork to keep your room warm. The compressor can become irreversibly damaged under this kind of operating condition, so it’s best not to switch to heat when snow completely covers the outdoor unit or when the outdoor temperature is below 15°C.

Does The AC Button Affect Heat?

Yes, the AC button affects heat. Air conditioners operate as heat pumps even when you use them to heat a room. Assuming air conditioners generate heat from a typical heating element, then the AC button won’t affect heat. However, air conditioners lack heating elements since they can transfer heat from outdoor to indoor by interchanging the function of the cold evaporator coil and the hot condenser coil. Kindly check the explanation below to see how the interchange of function between the evaporator coil and the condenser coil transfers heat indoor.

While in heat mode, the outdoor unit will extract outdoor heat and add it to the refrigerant. The refrigerant then circulates through the coil in the outdoor unit. The refrigerant will circulate until it gets to the compressor, where it will be pressurized. The refrigerant becomes hotter after the compressor pressurizes it, and it will move straight to the coil installed in the indoor unit.

A fan will blow air over the hot refrigerant as it circulates within the coil installed in the indoor unit. As a result, the hot refrigerant will begin to release heat to the room until its temperature becomes the same as the room’s temperature. When the refrigerant becomes cold enough, it will be forced back to the outdoor unit to re-absorb heat, and the cycle will keep on repeating itself until the room warms up to the set temperature.

The compressor will sustain the refrigerant’s continuous flow by pressurizing the refrigerant at the right time, and the compressor won’t function without the AC button. However, the AC button doesn’t affect heat in car AC since they don’t rely on outdoor heat to warm the car. Cars use the engine’s heat, and the temperature of a running engine is always hot enough to use air as a medium of convection.