THINGS TO CHECK IF THE INDOOR UNIT HAS WATER DRIPPING:
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Cooling coil drain pan clogged with algae.
We do not SELL these items This is a typical coil pan that has had the coil removed from it. You need not do this removal to clear the algae. A type of algae grows really well in the cool, dark, damp conditions inside the cooling coil drain pans. If the coil runs extra cool and the filtration is poor, the algae seems to grow more. Remove the front door panel of the evaporator coil and clean out as much of it as you can and then treat the pan with algaecide. You can get the tablet form of it from a local dealer. It works fairly well. Drain line from coil to outside or to sewer drain clogged.The most common stoppage of the drain line from the coil to the sewer is the trap. Heavy particles will settle to the bottom and eventually will clog. Just simply clean it out occasionally. Run a wire, flush with water, or blow air through it to clear the clog. TIP: One of the very best ways to clear the drain line and the sewer line it dumps into is to pour scalding hot water into it. Use a liberal amount. Look for the presence of two traps inline. An air trap will sooner or later happen and it will be as though the line is clogged. If you find a sag in the tubing that makes the equivalent of a trap plus a real trap or any multiple combination of either of these in the same line it is a problem. Make sure the line drains consistently downward and only has one trap.
Any time the drain is attached at a point on the system where it is on the suction side of the air flow, it must have a trap or sewer gasses may come up into the system and become very dangerous. This condition of suction can also cause the water to back-up in the line and cause an overflow of the pan. Trap it if it doesn't have one. If the evaporator iced and is thawing, it may run water from nearly any place. The system may have a dirty filter, restriction of air flow, be low on refrigerant, or have numerous causes for the icing. Refer to the menu and read the Refrigerants and Charging section where it is explained in great detail.
Sewer drain clogs may cause the condensation water from the air conditioner to back up and overflow. Use the hot water tip above to clear it. If the drain pan is rusted out, it is a serious problem and you will have to replace the cooling coil and pan most likely. There are no repairs for a rusted pan.




The most common stoppage of the drain line from the coil to the sewer is the trap.
Heavy particles will settle to the bottom and eventually will clog. Just simply clean
it out occasionally. Run a wire, flush with water, or blow air through it to clear the
clog.
TIP:
One of the very best ways to clear the drain line and the
sewer line it dumps into is to pour scalding hot water into it.
Use a liberal amount.
Look for the presence of two traps inline. An air trap will sooner or later happen
and it will be as though the line is clogged. If you find a sag in the tubing that makes
the equivalent of a trap plus a real trap or any multiple combination of either of these
in the same line it is a problem. Make sure the line drains consistently downward and
only has one trap.
Any time the drain is attached at a point on the system where it is on the suction
side of the air flow, it must have a trap or sewer gasses may come up into the system
and become very dangerous. This condition of suction can also cause the water to back-up
in the line and cause an overflow of the pan. Trap it if it doesn't have one.
If the evaporator iced and is thawing, it may run water from nearly any place.
The system may have a dirty filter, restriction of air flow, be low on refrigerant,
or have numerous causes for the icing.
Refer to the menu and read the Refrigerants and Charging section where it is
explained in great detail.