Why is the AC Unit in My Home Leaking?

June 18, 2018by admin

It’s that time of year again. It’s hotter than blazes outside, so you crank up your home air conditioning unit for sweet relief.

Uh oh…

Where’s all this water coming from?

If you see water leaking from your HVAC unit drain pan or compressor, don’t panic – most issues with home air conditioning units are maintenance related. But if you see water, remember to call in an HVAC professional, as it could be dangerous to investigate or try to fix the issue yourself. You could do damage to the unit, or even worse, injure yourself.

Here are 6 reasons why your air conditioning unit may be leaking (and how preventative maintenance can correct nearly all of them!).

Blocked drain line

The drain line is part of your HVAC unit that is actually supposed to leak, so if you see a small drip of water coming out of this pipe on the outside of your home, there’s no need for alarm.

The drain line removes condensation caused by the unit’s evaporator coil and deposits it outside the house. Over time, though, the drain can get clogged, sometimes with dirt, sometimes by insects, causing water to back up into the drain pan. The drain pan can only hold so much water, so if your drain line is clogged, eventually that water will spill over and cause water to leak inside your home where it shouldn’t.

This is usually one of the easier fixes with regular maintenance, when an HVAC professional will check and remove any blockages from the drain line before they cause damage.

The unit is low on refrigerant charge

Your HVAC unit needs refrigerant to cool the air in your home. Refrigerant absorbs the heat from the air inside your home and dispurses it outside.

If your refrigerant charge is low, the unit will freeze when it’s running. When the unit is low on refrigerant, the system expands more, lowering the temperature of the coil to freezing or below. This causes moisture from the air to form ice on the coil. Then when the coil starts to thaw, water drips as the ice melts.

Going through several cycles of this freezing and thawing not only increases the chance of damage to your home, it can also cause damage to your AC unit. Plus, low refrigerant rarely occurs in an air conditioning system in good condition, and can be a sign that your system needs service to find the leak.

Dirty filters are blocking the flow of air

Your unit can also freeze when your air conditioning filters need to be replaced. Fortunately, this is a very easy issue to prevent by swapping out your filters routinely.

If you don’t have pets, you should change your air filters about every 90 days. If you have a pet, change your filter about every 60 days. If you have multiple pets or someone in your home has allergies, you should change your filters every 20 to 45 days. Changing your air filter is a simple and inexpensive way to increase the efficiency and extend the life of your system.

Dirty coils are causing the unit to freeze

Coils collect dirt over time, but you can dramatically slow this process if you change your air filters regularly. An HVAC professional can also clean the coils during a routine maintenance visit.

The drain line is disconnected

If the PVC fittings weren’t properly installed, sometimes the drain line can become disconnected and leak. This is also something that an HVAC professional can easily catch and correct during routine maintenance.

Improper insulation

When you bring an icy cold glass of lemonade outside on a hot summer day, the glass starts to sweat with condensation. The same thing can happen with your duct work if it was not properly insulated, and that condensation can lead to water damage in your home. If your ductwork does double duty for heating in the colder months, proper insulation by an HVAC professional will make your heating more efficient and save you money, too.

As you can see, most of these issues are completely preventable with a little routine maintenance. If you do catch a leak from your HVAC system, call a pro in right away, as water damage to your home can be costly.

W.G. Speeks are Richmond, VA’s heating and cooling experts since 1943. Call us today at 804-276-2800 if you’ve found a leak that you need repaired or to schedule your home heating system for a checkup and maintenance appointment, to prevent future leaks.

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