HVAC condensate leak Columbus Ohio

Why is My Air Conditioner Leaking Water Inside the House?

When your air conditioner is humming along and cooling your home on a muggy summer day in central Ohio, you may see water leaking around the unit inside your home. Before pondering the reason, turn off the AC thermostat and mop up the water to prevent problems with mold and rot. The answer to your question will lie in just why water collects in your AC unit in the first place.

Moisture Condenses on Your Air Conditioner Evaporator Coils

An air conditioner cools incoming air as it passes over the evaporator coil, or A-coil. In a typical HVAC system, the A-coil is located just above the blower motor in the furnace. Refrigerant travels from the compressor outside, as a gas, and enters the A-coil. The blower motor blows air across the coil, sending cool air into your home. The refrigerant is converted back into a liquid, and transported back to the outside unit, to start the process over again. The refrigerant system is an enclosed system, and none of the gas or liquid should escape the system unintentionally. That’s not the liquid we’re talking about here, though. What causes the moisture is condensation on the outside of the coil as the coolant’s energy is release and the temperature changes.

You see this same thing when moisture condenses on a glass of iced lemonade or a glass of cold beer. Moisture forms on the outside of the coil, and drains off into a drain pan at the bottom of the coil, then out a drain tube to a floor drain or other drain. The water is supposed to drip onto a drain pan and then enter the condensate drain which is the PVC pipe (usually white) that takes the water out of your home to drip outside. Here are a few of the reasons why water leaks into your home.

Blocked Condensate Drain

If dirt, mold, dust, and sludge block your condensate drain, the water backs up and overflows the drain pan. At this point your best bet is to contact Dor-Mar Heating and Air Conditioning, your Columbus, Ohio HVAC service, for assistance. There are several ways to unplug the condensate drain but the best method is a professional vacuum to suck out the blocking material. The technician will also make sure that the PVC pipe is properly connected, draining appropriately, and not damaged. Older systems may have a drain tube dripping into a floor drain located near the furnace.

Rusted or Damaged Condensate Drain Pan

So, you have had your AC unit for more than a dozen years and now you are getting water leaking in to your home. If the condensate line is not blocked, the next most common reason for the leak is that your drainage pan has rusted or become damaged and water is leaking out of a hole. If your HVAC technician finds this problem you will simply need a new pan which can be easily installed.

The Condensate Pump Is Not Working

When your AC unit is located in the basement, the condensate water commonly needs to be pumped “up-hill” to get out of the house or into a basement drain. An old, damaged, broken, or never-serviced condensate pump will give out and then water collects in the condensate pan and overflows. The pump needs to be replaced by your central Ohio HVAC service.

Frozen Over Evaporator Coils

If your evaporator coils get too cold it will develop frost on the outside. When the AC is turned off that ice will melt and may overflow the condensate pan. The most typical reason for this happening: dirty air filters and the dirt is impeding air flow. When there is insufficient air flowing over the coil, they often freeze up. This is a problem that you can easily avoid by checking your air filter and changing it when dirty. During a hot and muggy central Ohio summer, check the filter once a month, at a minimum. Every three months is OK for the rest of the year.

Failing Blower Motor

If the blower motor on your furnace is not moving warm air across the coil, converting the refrigerant gas back into liquid, the system retains its cold and the coil will ice up. This is why we ask our customers to ensure their AC is completely off a couple of hours before their service appointment; the HVAC technician cannot work on a frozen system.

Low Refrigerant

The closed refrigerant system is pressurized to a particular level for it to function properly. It may surprise you to know that as your refrigerant level falls, there is a point at which the lower pressure in the AC system causes the coils to freeze up. This causes the same problem of freezing, melting, and overflowing.

Routine Air Conditioner Servicing Prevents Water Leaking into Your Home

So if your system isn’t blowing cold air, is frosting over, and/or  leaking water after you turn the air conditioner off, there could be a myriad of reasons. Your best bet is to schedule a visit from one of Dor-Mar Heating and Air Conditioning’s highly trained and certified HVAC service technicians to service your system before any of these events occur.

Discovering water on the floor near your AC system inside is not a catastrophic event! If you suspect any of the above symptoms, call today, or use our convenient online appointment request form.

About Dor-Mar Heating & Air Conditioning

In continuous operation since 1962, our expertise goes beyond just the mechanicals of your HVAC system. For top-notch service keeping your home’s heating and cooling system clean and your family breathing clean, filtered air, contact Dor-Mar today.

Our team offers a wide array of routine maintenance and emergency services for your heating and cooling system, allowing your family to breathe fresh, safe, clean air and be comfortable year-round. We also offer a number of add-ons to your HVAC equipment that can improve your home’s IAQ, such as electrostatic air filters, whole-house humidifiers, duct cleaning, Ultraviolet-C lighting systems, and more.

Schedule an appointment for HVAC system troubleshooting or maintenance with us today by using our online contact form, or call one of our seven neighborhood offices listed below. We pride ourselves on our customer-focused service, and our reviews show it.

NEWARK  740.345.6639 • COLUMBUS 614.238.6689 • DUBLIN 614.545.8939 • REYNOLDSBURG 614.365.1579 • WESTERVILLE 614.381.1540 • GROVE CITY 614.595.3098 • ZANESVILLE 740.454.2420

Dor-Mar…Your Climate Hero!

*Please note: neither the Centers for Disease Control(CDC), the World Health Organization (WHO), nor the manufacturer of our UV-C Devices have officially announced whether UV-C kills the current strain of Corona Virus (COVID-19). We urge you to err on the side of caution until we have a definitive answer, and take other measures to prevent the acquisition or spread of this virus.

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PLEASE NOTE: If you are a renter, please have your landlord/owner contact us directly to schedule service. We can only work with property owners.