Why isn't there drain holes in bottom of window air conditioner? I drilled a hole for water to drain. Is there a problem with this?

There technically isn't a drain pan in AC units. Some have a little hole in the back, some do not. If they do not, then the evaporator fan "slings" up the water accumulated from the condensation in the air, unto the coil to help cool the inside of the unit. If there is no hole, do not drill into the machine. You are likely to hit a sealed system component and damage the unit entirely.

Here is a thought, received by me from a AC mechanic recently. Window ACs no longer actually drain concensate. Rather, the water is caught in a pan with the idea it will evaporate back into the outside air. The reason for this is the dripping water frequently resulted in the growth of algae below the unit resulting is unsightly stains and sometimes, slippery conditions. Evidently, there were a lot of complaints about being 'dripped on' also. So, AC manufacturers don't put drain holes in the bottom any more. If the pan over fills, it will spill out of many makes. If you want yours to drain, put a hole in the bottom.

Like I said, just a thought.

Thanks for your question @ FixYa.com

The A/C has a drain crease in the bottom to drain water/condensate out the rear. If water is pooling, you can use a water hose and spray out this cease to unclog it. It helps for the A/c to tilt up inside with the outside part tilting down to drain. Now things that get in there to stop it up are, grass, (if mounted in a lower story window), leaves, bugs, pine needles. You may have to remove the outside case to clean all the debris out. Hope this helps Fix Ya up. Drilling a hole will help, but then what ever has stopped up the drain, will stop up your drill hole, and put you right back where we are today.

No drain holes on most units that size

The water gets from the front evaporator thru
a small hole you can not see

Then it finds it's way to the outside or back on the
bottom metal pan

It is evaporated by the condensor fan

It may drain out over the rear pan lip, if
it gets alot, but no drain hole is necessary

You can angle the unit down at the outside or
rear & you can drill a small hole, but it uses the water
to cool the condenser

From what you have described, it sounds like the drip pan under the unit is full of water. This can be caused by the unit not being installed properly in the window. It must have 1/4' to 1/2" downward tilt at the rear. This allows the water in the drip pan, to flow to the rear and drain away thru the drain hole. Also, the drain hole may be clogged and needs to be cleared. The drain hole can be a challenge to find sometimes, as the clog can blend in with the hole. Be patient and persistent when looking for the drain hole. A pipe cleaner can be used to clear it.

I hope this helps and thanks for choosing FixYa.

It shouldn't be a problem if you drilled the hole near the rear, outer edge of the drip pan and didn't accidentally pierce any of the mechanical above it. Also, be sure the rear of the unit is tilted down at least 1/4" to 1/2", so water will flow to it. Check the drain hole periodically, as they will become clogged over time.

Thanks for choosing FixYa.

There is no drain on some of the newer ones,that plug into a 110 outlet.Look on the bottom of the case,to the rear of the unit.If it has a drain the case will have a small hole in it.

Hi,
On many of the newer air conditioners they intentionally keep some water in there so that it splashes onto the condenser coil and helps to cool it....while this may work well it also creates more noise....so I often recommend to drill a drain hole in the back corner...jus drill down from the top...drilling up from the bottom is a great way to drill right through the coil....

heatman101

Hi,
Many newer units are made to retain the water a splash it onto the condenser coil...
you can drill a hole if the noise bothers you...

heatman101

These are designed to retain some water in the pan. This is for the slinger fan to throw water through the condensing coil. This helps the refrigerant cool and is important to the efficiency of the unit. I would certainly not recommend drilling a hole in the bottom. The hole may cause the water to roll somewhere where damage could occur. Try instead tipping the unit Backwards before bringing it in the house.