To run an air conditioner, you need to know how to power it when using an extension, especially when it comes to the wire size of the cord.
Air conditioners, like all other electrical home appliances, need to be powered by an electrical outlet to work.
An air conditioner is a big power consumer, both when starting it up and while it is in running mode. It is therefore important to ensure that they are powered up properly and safely.
Because of their size and large power consumption, air conditioners need to be powered up very specifically and carefully. Their huge capacities mean that they cannot be treated like other, simpler electrical appliances in the home.
Powering up air conditioners
Since air conditioners come in various sizes and cooling capacities, which are measured in British Thermal Units, (BTU) their power outlets need to be able to withstand their size.
Air conditioners require much more than simply being plugged into standard electrical power outlets.
Standard outlets cannot handle the amount of power air conditioners require to start up and run, which is why it is recommended that you have a dedicated circuit installed for the AC.
Extension cords can also be used when it is absolutely necessary, but they need to be the right size for the unit.
So, in the case of a 5 000 BTU air conditioner, what size wire should the extension cord have?
What size wire for a 5 000 BTU air conditioner extension?
When it comes to powering up an air conditioner the right way, the recommended approach is to have a dedicated circuit installed for it.
This is regarded as the safest way to plug in an air conditioner in at home in order to avoid any electrical hazards that may arise when a power outlet does not have the capacity to handle the electrical current of an air conditioner.
Extension cords can be used, but one needs to be careful about what type of extension cord they are using.
You cannot plug an air conditioner into any extension, it needs to be an extension that is designed to withstand the power demand of an appliance as large as an air conditioner.
A heavy-duty extension is built to take on the size and power of air conditioners, but they need to be the right size.
If you are going to use an extension, you should keep in mind that experts recommend that they should only be used temporarily.
If you are looking for the right wire size in an extension for a 5 000 BTU AC unit, you need to look at the wire gauge. The wire gauges that are typically used are 10 gauge, 12, gauge, 14 gauge, and 16-gauge wires.
A 5 000 BTU air conditioner requires a 10 gauge or 12 gauge extension cord.
The higher the wire gauge, the thinner the cord
The higher the gauge of the extension wire, the thinner the cord will be. Thicker cords are more beneficial as they can handle much larger currents such as those from air conditioners.
A 16-gauge extension cord is not the best option for powering a 5 000 BTU air conditioner (the smallest air conditioner size), as it is too thin to carry the current required by the 5 000 BTU AC unit (4 to 7 Amps of current).
The best extension cords to use for air conditioners
To ensure that the extension cord you want to use is safe to use with your air conditioner, it is safest to use an extension cord that was specifically designed to be used with high-power appliances, such as:
| Extension cord | Where to buy | Length | Wire size | Price |
| Heavy Duty Air Conditioner and Major Appliance Extension Cord Wire |   |
12 feet | 14-gauge | $17.99 |
| Buy it on Amazon | ||||
| POWTECH Heavy duty Air Conditioner and Major Appliance Extension Cord |   |
12 feet | 14-gauge | $15.39 |
| Buy it on Amazon |
Does the length of the extension cord matter?
Since a thicker extension cord is necessary for powering a 5 000 BTU air conditioner, it is also important to note that the thicker the extension is, the shorter the wire should be for the electrical current to travel through it properly.
This is why it is recommended that if an extension is going to be used for an air conditioner, it should be as short as possible. Extensions come in lengths shorter than 10 feet and can be up to 20 feet or longer.
How to safely use the extension
The general recommendation is that an extension cord should not be used for an air conditioner, unless it is absolutely necessary, and a dedicated circuit cannot be installed.
Since it is fundamental that you know how to safely use the extension, here are a few tips:
- Unplug the extension if it becomes too hot to touch
- Cover unused receptacles with plastic or child-proofing covers
- Never bend the wire while in use
- Do not pass the extension through furniture, carpets, or rugs
- Make sure you are using an indoor extension
- Never remove the grounding pin from the extension
- Avoid having other appliances plugged in with the air conditioner