Why Window AC Full of Water After the Rain?

Under normal circumstances, your window air conditioner will be producing a small amount of water. However, the unit should never be full of it.

During rain, your window AC removes more moisture from the air; consequently, more condensation is created. If this extra moisture gets drained after the rain is over, then everything’s fine, but this won’t happen if the drain hole is clogged or if the unit is not positioned correctly.

Why Window AC Full of Water After the Rain?

If your window AC is functioning properly, then there shouldn’t be any water in it after the rain. Under normal circumstances, the excess water should get drained from the system.

An air conditioner that is full of water was most likely not installed at the right angle or it has a clogged drain hole.

Even though rain can’t cause any damage to the AC, standing water might end up harming the equipment. If water gets left in the air-con for long enough, the metal parts will start to corrode and the electric components might go bad.

Window AC Sounds Like Water After Rain

If your window air conditioner always sounds like there is running water inside it, then you have nothing to worry about. Air-cons remove humidity from the room and the condensation will either get removed from the unit through the drain or will get ‘spit’ onto the coils.

However, if this noise is unusual for your air conditioner, then it looks like some water has gotten inside the unit after the rain, or the condensation didn’t get drained at all. The water might have built high enough to hit the spinning fan – and that’s exactly what you’d be hearing.

Read: Is It OK To Leave Window AC On All Day?

How Do You Get Rain Water Out of an Air Conditioner?

  • Inspect the drain hole – it is usually located at the bottom of the unit (close to the back). The drain pan can collect debris and, at some point, algae might start growing in it; simply clean the pan and unblock the drain hole.
  • Water won’t be able to flow out of the unit if it’s not slightly tilted. Make sure that the air conditioner is tilted backward – this will allow rainwater and condensation to drain out of the unit.

Why Does My Window AC Leak Water When It Rains?

The air conditioner is not properly sealed in the window

In such a case, the actual rain might be able to make its way into your house. Moreover, more warm outside air will be entering the air-con and this will lead to excess moisture build-up inside the unit.

The drain is blocked

Your air conditioner has to remove quite a lot of moisture from the air, especially when it’s raining. If the drain holes are clogged, then the water that would normally get removed from the unit will get trapped inside (at one point, the air-con will start leaking).

The outside air has too much moisture in it

When it’s raining, your air conditioner will accumulate excess moisture inside – and that is completely normal. A lot of window units will also start leaking water, but if you have a drain pan, it shouldn’t become a huge inconvenience. 

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Read: Why Window AC Compressor Turns On And Off?

Should Window AC Have Water in It?

Your window air conditioner should have a tiny amount of water in it, in case it’s operating properly. These units do not only cool the air, but they also remove moisture and get rid of it with the help of a drain.

In fact, on a hot day, you can expect your window AC to create over 2 gallons of condensate

Why Do Window AC Units Hold Water?

Water can collect in the base pan of the unit. Some of it will get thrown back on the coils, while the excess condensation should get drained from the AC.

Sometimes, the water will drain away only once it reaches a certain level. 

Should a Window Air Conditioner Have Water in the Bottom?

Modern window ACs usually collect the condensation at the bottom of the unit in a special tray and then reuse the water when it’s needed. However, during rain or on extra humid days, this tray might fill up too quickly – this is when the excess water would get drained from a hole located on the side of the tray.

So, it is normal for an air-con to have water in the bottom, and it’s actually okay for it to overflow a bit on a humid day. But if this happens too often or even on dry days, then your unit has a drainage issue. 

Read: Why Are HVAC Vents Under Windows?

What Are the Symptoms of a Clogged AC Drain Line?

  • There is a musty smell near the unit
  • There is water leaking around the AC
  • The window air conditioner is no longer able to effectively cool the space
  • The AC unexpectedly shuts down or doesn’t turn on at all

How Do You Unclog a Window Air Conditioner Drain Line?

Ideally, you would want to remove the unit from the window. Don’t forget to place a thick cloth over the AC’s ‘sensitive’ parts (the switches and the motor) to prevent water from causing damage to the elements.

Where Is the Drain Line on My Window AC Unit?

Window air conditioners don’t exactly have a drain line as these units are compact and they don’t need to push the condensation as far as central units, for example.

They do have drainage holes that can be typically found underneath the exterior part of your unit (the part that hangs out of the window).

Do All Window Air Conditioners Have a Drain Hole?

Some window units do not have a hole as the condensation gets collected in a pan and then is reused in the system. However, the units that don’t have an open drain hole will typically feature a slinger ring.

If the slinger ring isn’t draining properly, you usually have the option of unplugging the holes.

Read: How Reliable Multi-Zone HVAC Systems Are?

Why Is My Window AC Not Dripping Water?

If your window air-con is not draining water, it either means that the unit’s drain is clogged or that the air conditioner is improperly positioned.

Does Rain Affect Window Air Conditioners?

Any type of air conditioner can’t really get damaged by rain. However, standing water, strong winds, and lightning can affect the cooling equipment

Why Is My AC Not Working After It Rained?

  • The coil is frozen
  • The unit got damaged by something (a falling branch, for example)
  • The air conditioner got clogged with debris

Can You Repair an Air Conditioner in the Rain?

If you can remove the unit from the window and place it inside, then you can certainly repair the air-con even if it’s raining outside.

But trying to service the unit while a part of it is outdoors during rain is not recommended as moisture can cause damage to the unit’s sensitive parts and it’s obviously dangerous working on electrical components while there is water around you.

Read: What Are Types Of HVAC Systems In Hotels?

Should You Turn Off Window Air Conditioner During Storm?

It is recommended to turn the window unit off during a thunderstorm. If it is possible, taking the unit inside is also advised.

During a storm, a window AC can get struck by lightning and damaged by a flying object or by a power surge.