How to Recharge a Window Air Conditioner: The Definitive Guide (2023)

window air conditioner

Recharging a window air conditioner isn’t as difficult as it might seem in the first place. This is one of the most common problems when it comes to poor operation of the appliance. So, if your AC stops working or lacks intensity, it’s probably out of coolant or there’s a leak. To fix the issue, you simply have to refill it with a new portion of Freon.

Make sure you schedule regular HVAC maintenance, so check on yours every couple of months. In this guide, we are going to tell you how to recharge a window AC unit.

What You Need to Recharge a Window AC

In case your AC uses Freon as a refrigerant, you’ll only need one thing for a refill. You can find it online or at any local maintenance store, and it’s called a Freon kit. It contains everything you need for maintenance. Take note that there must be a set of instructions coming with the kit. Read those carefully and follow precisely since Freon is poisonous and has to be used with extreme caution.

Pay attention to the laws of your state as well. Some don’t allow interfering in the work of any refrigerating system unless you’re a certified professional.

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A Step-By-Step Guide on Refilling Your AC

If using a specialized kit, you’ll finish maintenance in 5 steps:

  1. Unplug the AC. First of all, no matter which appliance we’re talking about, you have to make sure it’s off and unplug it. This will make sure you don’t electrocute yourself and open the unit while it’s on;
  2. Open the unit. Here you may need a screwdriver that doesn’t usually come with the kit, so be sure you have one. Find a manual you’ve got with your unit to find out how guidelines for correct handling of every detail;
  3. Do an integrity check. All elements of the construction have to be intact. If you notice a leakage or any signs of damage, fix them if you know how. In case you don’t, contact a specialist for help;
  4. Attach necessary valves from the kit. Your kit contains two valves that have to be attached to the compressor and the Freon source. This allows you to refill the AC unit fast. Make sure you find out how much refrigerant you’ll need eventually. All information about the compressor location and amount of Freon needed should be in the User Manual for your unit.
  5. Refill. Only after you’re 100% sure everything’s intact and secured, plug your AC in and turn it on. Adjust to the strongest setting for faster results. You don’t have to do anything else for a refill, it will occur naturally. Your mission now is to turn off and unplug the air conditioner once you get the necessary amount of Freon in.

After all, you will only have to remove the valves and put your kit in a safe, dark place if there’s anything left.

Read also: Portable Air Conditioner Vs Window Unit


Recharging a window air conditioner isn’t difficult if you have a Freon kit and follow every instruction with caution. If your state allows it, go ahead and fix the problem yourself. There are some tips and tricks you should consider following along the way to make sure the operation is successful.

Also, don’t forget about regular maintenance of all your appliances, and call a local service if you can. A certified expert will make sure there are no potential issues you’ll later need the kit or anything else to fix.