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Althoff Home Services Blog

Why Does My A/C Have Ice on It in the Summer?

There’s nothing that’ll get you more steamed than coming home to a hot house in the summer. Imagine your surprise when you go to inspect your air conditioner, and it’s covered in ice! Each summer, this is one of the most common calls we get at Althoff Industries.

Luckily, an icy air conditioner is easy to diagnose and repair. While it may seem like you’ll have an expensive repair bill coming your way, oftentimes you simply need to make a few simple changes to prevent your air conditioner from icing over. In this article, we’ll identify the causes of most frozen air conditioners, the repair process and how to prevent your air conditioner from freezing in the future.

Warning: If you notice ice building up on your air conditioner, turn off the unit immediately. To prevent additional damage from occurring, do not turn on the air conditioner until the ice has melted and you have located the cause. If you’re unsure of the issue causing your air conditioner to freeze, contact us to schedule an appointment.

Reduced Air Flow

One of the common culprits we discover when investigating frozen air conditioners is reduced air flow. Usually, this is one of the first issues we look for, since it’s one of the easiest to correct and cheaper for homeowners to repair. Reduced air flow could be caused by any of the following:

  • Dirty air filter. It’s important to inspect and replace your system’s air filter regularly. It’s a relatively inexpensive home ownership task, but you can end up with a hefty repair bill if you don’t keep up with the maintenance. When you have a dirty air filter, your system has to work extra hard to move the air through your home. This causes your air conditioner to work overtime, which may lead to ice buildup on the compressor, among other issues.
  • Too many closed air registers. You might think you’re doing yourself a favor by closing air registers and saving yourself a few dollars on your summer cooling bill. Unfortunately, when you close too many registers, you reduce the amount of airflow below the amount required to optimally run your home’s cooling system, which can cause the condenser to freeze. Make sure at least 75% of your air registers are open at all times.
  • Damaged air ducts. Depending on where they’re located, in a wall, basement or even closet, your system air ducts can take a beating when you’re moving heavy equipment or doing home repairs. If you end up damaging a duct, you can decrease the airflow.
  • Decreased fan speed. Over time, your system can get worn down, and your fan speed can decrease. On the other hand, your system’s fan speed may not have been set fast enough to begin with. If you’ve tried all other air flow repair methods without any luck, a technician can help you determine if the fan speed is freezing your air conditioner.

Faulty Thermostat

If your system is having trouble regulating the temperature, you waste money, energy, and odds are, your air conditioner is freezing over. When your system can’t properly regulate temperature, it’s running constantly, even when it’s cold out at night. As your condenser works overtime, the coils can build up condensation and eventually freeze over. If you notice your system is running even when it’s cool outside, your thermostat could be the culprit. A professional can help you test your thermostat and pinpoint the issue.

Drainage Problems

In addition to keeping your house cool, your air conditioner extracts humidity from the air to make your home’s air more comfortable. This excess moisture needs somewhere to go if it’s not in the air. Your air conditioning system should have a drainage pipe attached that carries moisture away from the unit. If this pipe becomes blocked, the water can get stuck in the unit and freeze. Ensure your system drain is clear and removing moisture efficiently.

Similar drainage problems can occur if you have a window unit that’s freezing up. To drain properly, window unit air conditioners must be tilted at a slight angle out of the window to allow water to drain. If your window unit is freezing up, ensure the air conditioner is tilted according to the manufacturer’s installation instructions, and check that no debris are blocking the drainage hole. 

Low Refrigerant

You might have never have guessed, but having low refrigerant can actually make your evaporator coil freeze. Seems weird, right? If you don’t have the proper amount of refrigerant in your A/C system, it has to work harder to cool your home. When your unit is working too hard, icing is likely to occur. Typically, low refrigerant is a sign of a leak in the system. You can usually identify a leak by listening for a hissing or gurgling sound coming from the condenser. If you suspect a leak, it’s time to call a professional to help repair the leak and recharge the system with refrigerant.

Is Your Air Conditioner Putting a Freeze on Your Summer Fun?

The experts at Althoff Industries can help you identify why your air conditioner is freezing and repair the issue. Don’t let a frozen air conditioner prevent you from staying cool during the summer, give us a call at 815-900-5002, and schedule your appointment today!

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