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Can’t feel your window AC letting out that cool breeze like it used to? Could it be that your refrigerant is leaking? If so, you may need to recharge it. Read on for a detailed guide on AC recharging.
Does a window air conditioner need recharging?
Under normal circumstances, a window AC doesn’t need to be recharged over the course of its lifetime. However, a leak within the AC’s refrigerant system may necessitate a recharge. Some of the signs that your AC unit is leaking refrigerant and that a recharge is necessary include:
Frost on the AC Unit
It’s not unusual to see frosty coiled pipes inside your AC unit, as they’re part of the refrigeration system that’s responsible for air cooling. However, if the frostiness extends to the outer parts of the AC unit, it’s highly likely that the refrigerant system is leaking.
AC Blowing Warm Air
You’ll know your AC is not cooling and blowing room temperature air if you’re still feeling sweaty and uncomfortable even with the AC turned on. While this may also be caused by a thermostat failure, it can also be due to a refrigerant leak. Once there’s a leak, the refrigerant level drop too low to support proper air cooling. This results in your AC vents blowing out warm air. If you notice that your window AC is blowing out room temperature air, you should consider a recharge.
How to Recharge a Window Air Conditioner
AC recharging is a complicated and dangerous process that should only be undertaken by certified HVAC technicians. Some states have even outlawed refilling of AC refrigerants if you’re not approved by the relevant bodies. Therefore, before you go about opening your unit to recharge, make sure you’re on the right side of the law- depending on where you reside. The proper process for recharging a window AC is as detailed below:
To avoid putting yourself in harm’s way, ensure you have the proper personal protective gear. These include protective goggles and hand gloves. You’ll also need the right tools and supplies for the job; including a screwdriver, a leak detector, and a refrigerant kit. Once you have these, you can now recharge a window AC unit.
1. Turn off and open the AC system
Before opening your AC unit, ensure to unplug it from the mains. Then, wear the aforementioned protective equipment to protect yourself from the Freon refrigerant that you’ll be refilling- as it’s highly toxic and cryogenic.
Next, it’s time to open the AC and inspect it for leaks. Most modern AC units have to be unscrewed open. If it’s an older AC version, however, you may simply have to slide the front end over. If you’re unsure of the proper method for opening your window AC system, consult the manufacturer’s instruction manual.
2. Inspect the AC for leaks
There are multiple methods that you can use to determine whether your AC refrigerant is leaking. For instance, you can simply apply a soap solution on the transmission gear of the refrigerant system and observe what happens next. Wherever bubbles form on the transmission gear, you can conclude that that’s a leaking spot.
Alternatively, you can use a leak detector tool, which works by sending out audio or visual signal feedback in case it detects a leak near the outdoor unit of your AC. Other less-common yet effective ways of detecting AC refrigerant leaks include the use of nitrogen to track changes in refrigerant pressure over time, and the use of fluorescent dye to detect the leaking spots.
3. Repair the Leaks
If there are only one or two leaking spots that can quickly be fixed by soldering, then go ahead and do so. However, for severe leaks, we recommend replacing your entire A/C unit- as that would be the relatively cheaper option.
4. Link the valves to the compressor
Once you’ve sealed up the leaking spots, it’s now time to open up your refrigerant kit and attach the two compressor lines to the service valve and tap valve on the kit. If you can’t locate the AC’s compressor, refer to your manufacturer’s manual.
5. Link the valves to the Freon kit
After connecting your service and tap valves to the compressor lines, attach the valves to the corresponding spots on the refrigerant kit. Your Freon kit will come with instructions on how to properly connect these valves to the kit. Also, be sure that your AC is actually using Freon before going to the effort.
6. Proceed to recharge the AC
The final step is to refill your AC with refrigerant by connecting the AC to the power system and turning it on. This will trigger the Freon to begin flowing from the refrigerant kit into the AC unit. Once the Freon kit’s gauge indicates that the AC has reached its refrigerant limit, unplug the AC, disconnect the valves and kit from the compressor, and then plug back your AC again for normal air cooling.
Cost of recharging a window AC
The amount you’ll get charged for a window AC recharge will depend on the pricing rates of the particular HVAC contractor that you’ll be hiring. However, the average cost for a window AC refill is ~$100 dollars. The average hourly rate for an AC tech- meanwhile- is ~$30 dollars per hour.
Remember, however, that HVAC technicians charge for labor as well. Therefore, if you want to recharge your AC unit for a cheaper price, consider doing it by yourself. In this case, you’ll only have to spend on the refrigerant replacement kit, which costs only ~$30 dollars on average.
Recharging vs Cleaning: Which One Do You Need?
Recharging and cleaning an AC unit are both important AC maintenance processes. A recharge will improve your AC’s functioning by replenishing refrigerant that’s been lost due to leaks; while cleaning the air filters and condenser coils is just as important to an AC’s proper functioning.
The difference, however, is that recharging is more of a long-term HVAC maintenance solution and may only have to be done once or twice over the lifetime of an AC system. AC cleaning, on the other hand, should be done periodically for proper AC functioning. You can reach out to an HVAC professional to tell you which maintenance option is needed for your particular situation.
HVAC tech with over 30 years of experience. Retired and doing repair work on the side around Madison County, AL.