Clogged AC Drip Pan Drain

[Retired2]

The hose drain is connected to the drip pan with a strange elbow type fitting.

This fitting is in a very in-accessible place. It is getting clogged with what i

assume is moss or whatever is growing on the bottom of the pan.

A drain snake gets hung up in this crazy fitting.

Any suggestions on what i could clean it with ? It is about a three quarter hole and fitting.......

and VERY difficult to reach.

[Farma]

The maintenance people in my work accommodation use pressure from a nearly empty bottle that they recharge aircons with. They use a flexible hose attached the bottle, poke it into the blocked drain then blast the line clear.

[Pacificperson]

A wet/dry vacuum with a short length of small diameter vinyl hose attached. You can attach the smaller hose to the vacuum hose with duct tape. The small hose can reach to the back of the unit. If necessary, reverse the hose on the vacuum unit and blow the fitting out.

[lopburi3]

DIY with small plastic hose and your mouth. Good control of pressure that way and you will feel if it clears. But are you sure that is where the blockage is? It could be inside pipe - especially if running with only slight dip as your fitting might indicate. Often easier to access outside drain near end and blow up (even if a bit messy in AC unit). You might find the pipe is full of water and blockage is at its end underground.

[Pib]

AC folks use pressurized air/water to clean/clear the drain pipe. I do the same thing with a home made device which is a small flexible hose (the kind they use in water filter hookup devices which is about pencil size in diameter) and I secured one end to an approx one liter plastic bottle (drill a hole in the bottle's screw-on cap and then used silicone and tape to secure the hose). I use a large Pepsi plastic bottle. The length of the hose is about a half a meter...enough to snake it from the drain pan outlet hole and down the drain pile a little distance....enough to get to/pass the first curve in the drain pipe where the blockage usually occurs. That length could be longer but usually I can't get past the 90 degree angle in the drain pipe which is about a third of meter from the drain pan. The mixture I put in the bottle is about 25% bleach (to kill algae) and 75% water. Once I snake/work the small flexible hose down the drain pipe and pull in back and forth a few times which is usually enough to clear the blockage I then start "squeezing" the bottle to create some pressure behind the liquid. Works good.

A lot of the flexible A/C drain pipe is kinda like a vacuum cleaner hose in having wire wrapped with rubber which creates a ribbed hose so getting even a flexible smaller snake hose past say a 90 degree curve can be very hard to impossible sometimes because the flexible snake gets hung-up on the drain pipe's ribs. Don't use great force in trying to push the snake past this point as you may puncture the drain hose...just just lite force, twist-turn, wiggle the snake to see if you can get it past that point. Use pressured water/air on that point.

The one AC which pretty runs 24/7 I usually have to clean the drain pipe at least twice a year because lizard dung, bugs, etc., mixed in the the normal evaporator drip water just clogs/restricts the drain pipe enough either at the drain pan exit hole or in the drain hose sharp curve to cause my evaporator inside unit to start dripping water n the floor. Out comes my trusty squeeze bottle with plastic snake hose device and I use it....5 minutes later I'm good to go for another 6 months or so....just avoided another AC repairman visit and cost.

[Retired2]

Thank you all for the great suggestions.

This morning I connected the drain pipe to my super suction wet/dry vacuum.

It pulled about a quarter cup of mossy sludge from the pipe and fitting and pan.

In the future, i am going to treat it will a bleach solution.

[MotoX]

Over the last 3 month's I repaired both of my A/C's having the same problem. I bought a "large" squeeze bottle like you see in restaurants for Ketchup, and Chili Sauce. Near the A/C where the drain pipe connects on one of my units I disconnected the line and forced water with about 20% bleach into the drain pan, and down the drain pipe. This scum is just gooey mold and dust. My 2nd A/C unit I opened up the same connection after it's exit through the wall to the outside and did the same procedure. If about once or twice a year you do this, your drain will never clog again.
The bleach is the best because if you just clean out the line with a snake, the mold will continue growing and clog up your drain much quicker.
In America homes have whole house systems and need a condensation pump to pump out the water. In that case I just added bleach/water every few month's to the condensation pump reservoir.