5 Possible Reasons Your Air Conditioner is Leaking Water

Here are the five most common causes of water leaking from your indoor air conditioning unit.

Any malfunction of your air conditioning unit can be very annoying, especially if it means you have to interrupt its use and call an HVAC technician to fix it. If you notice water leakage from your indoor unit, unfortunately, it means just that: turn it off until you are able to identify and solve the problem that causes the leak. Otherwise, you are likely in for more expensive air conditioning repairs very soon. 

Here are the five most common causes of water leaking from your indoor air conditioning unit. Some of the problems can be solved easily at home, but if you eliminated those options, it is best to call in the HVAC professionals and prevent further damage.

The Drain Line Is Clogged

The drain line is the pipe (usually white) that connects your indoor unit to the outside, leading the water resulted from condensation to drain safely. If this pipe is clogged, the water will have nowhere else to go, and it will come out through your indoor unit openings. Algae, dust, mold, and other debris can clog your pipe, which can be prevented by cleaning the pipe with white vinegar every six months or so. You may consider using a wet/dry vacuum cleaner to unclog a drain pipe or call an HVAC company.

The Drain Pan Has Holes or Cracks

The drain pan is a pan (or, better said, a pair of pans – one fixed and one removable) that collects the condensed water droplets from the evaporator coils. If one of the pans is cracked, has a hole, or is missing completely, the water will not be redirected through the drain line. Check that the pans are in good shape and not misplaced or broken. 

The Pump Does Not Work Anymore

If the AC indoor unit is in your basement, then one possible problem could be a malfunctioning water pump. This is a pump that pushes the water through the drainpipe safely toward the outside to allow it to be discarded properly. Check if the pump is working at all before you investigate other causes.

Poor Maintenance of the Unit (Old Air Filters)

The water leak may simply be caused by poor maintenance of the unit. If you forgot or neglected to replace or clean the air filters, the air will not flow correctly, leading to issues like frozen evaporator coils. When this happens, the drain pan will overflow and leak water indoors. Replace the air filter and check if the unit works properly afterward.

Refrigerant Leakage

Another possible cause of the evaporator coils freezing over is a low level of refrigerant (most often, air conditioners use freon.) Refrigerant in your HVAC system is not a substance that you need to add to from time to time. Its level should be the same all the time, so a refrigerant leak is an important issue that should not be overlooked. Some units have self-diagnosing functions, but if yours doesn’t, it’s best to call a professional to check. 

If you are still not sure what is causing your water leak and routine maintenance did not solve it, it is time to get in touch with an HVAC professional for assistance.

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