System and method for draining water from an air-conditioner

A method of operating an air-conditioner having an indoor coil, an outdoor coil, a drain pan, and a fan, the method comprising:

• determining that the air-conditioner is operating in a heating mode;
• detecting one of an internal temperature inside the air-conditioner and an outdoor temperature outside the air-conditioner as a detected temperature;
• determining that the detected temperature is below a threshold temperature;
• and
• pumping liquid settled in the drain pan out of the drain pan after determining that the detected temperature is below the threshold temperature;
• wherein
• the liquid is pumped from a pumping depth in the drain pan below a reference level,
• the pumping depth is lower than a slinging depth in the drain pan below the reference level,
• the slinging depth is a depth at which fan blades of the fan will contact liquid gathered in the drain pan, and
• the reference level is a level of the drain pan on which at least one of the indoor coil and the outdoor coil rests.

A method of cleaning an operating an air-conditioner having an indoor coil, an outdoor coil, and a drain pan, the method comprising:

• spraying an undiluted cleaning solution on the indoor coil;
• activating the air-conditioner in a cooling mode at a start time such that the indoor coil operates to draw heat from incoming air;
• gathering undiluted cleaning solution dripping from the indoor coil and condensate dripping from the indoor coil in the drain pan to form a diluted solution;
• turning on a drain pump to repeatedly pump the diluted solution from the drain pan onto the indoor coil from the starting time to a first time after the starting time when a current level of the diluted solution in the drain pan exceeds a first threshold level;
• continually gathering the diluted solution dripping from the indoor coil and the condensate dripping from the indoor coil in the drain pan from the starting time to the first time to update the diluted solution such that the ratio of cleaning solution to water in the diluted solution continually drops;
• repeatedly moving the diluted solution from the drain pan onto the indoor coil from the starting time to the first time when the current level of the diluted solution in the drain pan exceeds a second threshold level;
• turning off the drain pump at the first time;
• continually gathering the condensate dripping from the indoor coil in the drain pan from the first time to a second time after the first time to update the diluted solution such that the ratio of cleaning solution to water in the diluted solution continually drops;
• repeatedly moving the diluted solution from the drain pan onto the outdoor coil from the first time to the second time when the current level of the diluted solution in the drain pan exceeds the second threshold level;
• and
• turning off the air-conditioner at the second time,
• wherein
• the first threshold level is lower than the second threshold level.