We have air conditioners to breathe clean air. Removing moisture from the room, conditioners create a lot of water. This water removed from the air during operation falls down the cooling coil and drops into the base. Then it follows channels or passages to the rear of air conditioner. But some of the water is lifted up by the fan blade and used to cool the heating coil, while most proceeds to the rear. Once at the rear it drops out of the base and onto the ground. If everything is working perfectly, then such process runs every time.
As for window air conditioners, they can leak water. It is difficult to find the cause of this problem, that's why, you have to presume all suggestions of the most common reasons. Consider the following ones.
Improperly Installation
The water should be removed from the room to drain to the back of the machine. And for this, a window air conditioner must be slightly lower at the rear than the front. The difference of one inch is sufficient. So, this is your first task to check it. Some of them are improperly installed in the haste to get relief from the heat. It can be installed too low at front, then the water will flow into the room rather than outside. But if it is installed too low at rear, water can roll out front edges before has chance to exit towards rear drain.
Icing Up
In case there are problems with the cooling system, then water being de-humidified can turn to ice. Many reasons may cause producing ice. Try to remove front grille while machine is operating. And if ice is present on the cooling coil, then you will probably need service.
Air Leakage Around Air Conditioner
The warm air can enter around the air conditioner, then it will encounter cooler, dryer air. Condensation will occur in that way when they meet. If water leaking from front of air conditioner inspect to see if dripping from body of machine, or water droplets clinging to front area. You can test it. In this way, operate machine for 30 minutes and then use flashlight to check under front edge of base. Small water droplets here indicate an air leakage problem. So, add foam insulation to stop warm air from infiltrating.
Drain Hole Blocked
There is a drain hole or groove at the rear of air conditioner base that allows water to escape. If becomes blocked water can back up. Operate machine for 30 minutes and then inspect if draining properly. Use a small piece of wood to open drain hole at rear of metal base if appears blocked. But never be tempted to drill holes into the air conditioner body to relieve water pooling. Severe damage can result.
Internal Drains Blocked
Small passageways allow water to drain from front of air conditioner to the rear. They can become blocked and it may cause water poolling at front of machine and overflowing onto floor. In this case, you have to remove the air conditioner from window and service it.
Outside Temperature Too Cold
Outside temperature may be too cold at end of cooling season. It may cause the icing up of cooling coil. The problem may be the following: no leakage at bedtime but water in front of machine in morning. In this case, turn off machine before bedtime and restart as day warms. Operate machine at night with selector switch in "fan only" position. When doing this, room air will be circulated during night but not allow cooling.
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