When Is It Time To Replace A Window Unit AC?

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A questionable smell, an odd noise, or just the feeling that your window AC unit isn't keeping the space as cool as it used to can set off the mental alarm bells. Does it need to be replaced, or can it be taken care of with simple maintenance? Although you may dread the day when it makes more sense to replace the whole unit than to help it with maintenance tasks or repairs, it's crucial to know when that time has come so you're not stuck with unsafe indoor temperatures or untenable electricity bills. It's time to replace a window AC when it needs repairs that won't be cost effective, when it consumes too high a share of your energy bill, or when the issues are a risk to the health and safety of you and those in your household.

The length of time you've had the air conditioner can also be a helpful gauge of when to replace it. They tend to last for eight to 10 years on average –- even though they can last longer with attentive maintenance, if the unit is malfunctioning and it's been 10 or more years since it was installed, it's likely a replacement is needed. Window unit air conditioners work by cooling and dehumidifying the hot air inside. A thermostat, blower, and cooling coils work together to accomplish this, but all of these components can wear down over time. Units that are between one and five years old are likely to be covered by a warranty. If you see anything amiss in that time span, it's worth contacting the manufacturer to see if repairs would be covered. But outside of that general range, it's important to weigh the costs and benefits of whether repair or replacement is best.

When you see much higher monthly energy usage and costs tied to your AC running in the warmer seasons, it's time to think about replacing it. A newer unit — particularly one rated by the ENERGY STAR program — can correct this problem and help you reduce your energy costs at home. Other signals you need to replace the AC have more to do with how it's functioning or point to health and safety issues that cleaning won't help. Sounds like scraping or squealing coming from the air conditioner may mean there's a problem with an interior component. Also, if your unit has a musty smell that won't go away after cleaning the AC coils and filter, mold could be growing in a part of it you can't reach, which presents a risk to your respiratory health. Finally, if the AC is blowing out hot air or no cool air at all, it's a red flag that could be dangerous in a heat wave.

The cost to repair a malfunction in the air conditioner, remove mold growth, or replace depleted refrigerant could be costly, so after you observe serious issues, it's time to weigh whether the unit can be fixed or needs to be replaced. Start by gathering information on the repair costs, whether through searching online, asking a knowledgeable person in your family or community, or contacting a technician. If you find the expenses to repair it will come to 25% or more of the cost of getting a new one, replacing it might be the right call.

If you want to get every bit of usefulness out of your window air conditioner, stay on that train of thought: replacing the whole unit is a last resort as maintenance can take care of some common issues. If the air flow is still cool but seems weaker, it's possible the problem could be remedied by cleaning or replacing the filters which may have become clogged or dirty. Give the filters a thorough inspection if you notice this issue. Small gaps between the AC and the window may also be causing warm air to get in. This can be addressed by placing some weather stripping, like the Wintcomfort window air conditioner foam seal strip, around the unit. 

Even if your AC is still doing well, you'll want to maintain it, preventing dust from building up that affects its efficiency over time. Luckily, cleaning a window AC unit without removing it is doable. From inside the home, you can remove the grill and access the filter and coils, which need to be kept free of dust and mold buildup for the best functioning. The filters are usually positioned right behind the grill, which faces the inside of the room, and they should be cleaned or replaced monthly when you're using the air conditioner often.