Mini split dripping down the wall

[SALIV8]

Well this is my first mini split problem. And I’m stumped.

There was about 4 or 5 short drips down the wall (maybe 12”-14” long) on the center/left side of this idu. It appeared to be a yellow light oily substance and I immediately thought refrigerant leak. Then I thought the drain plug might be weeping since I swapped drain locations from this side to the right side. Or maybe fan bearing or fan motor oil (if there is such a thing?)

I bought a cheap leak detector and didnt get any hits.

I shop vacced out the drain line, and removed the mini split plastic housing to see if there were any other signs where it was coming from, or more drips behind the plastic.

Nothing obvious was there? There are no signs of an active drip. How can this be? Im stumped. These drips appeared more than 2 cooling seasons after I installed this system. This is the only idu that is doing this out of 7.

This idu, like the others, was pressurized when I removed the factory flare plugs.

At this point it is now a wait and see if it re occurs because I am out of ideas.

Heres some pics. Anybody have any thoughts to help solve this mystery?

 

[fitter30]

Look at the blower wheel is it dirty. Whole unit might need to be cleaned if it is. Condensate could be dripping of the coil and not into the pan.

 

[SALIV8]

Blower wheel was clean. Had very minimal dust spots on it. Coil was immaculate and the the condensate pan (what i could see of it) was spotless. I looked all around the hidden part of the unit and it was well insulated.

 

[shade]

I noticed on mine when i installed it i pulled too hard on the drain hose. it was barely hanging onto the plastic piece where condensate drains from.
Its held on by a metal clip. I bent the clip to hold harder and readjusted the hose back on.
check the actual connection may be coming from there

 

[SALIV8]

I checked the drain connection and it wasnt loose but i did snap the ring lock in place it did slightly move.

 

[MattT]

There was about 4 or 5 short drips down the wall (maybe 12”-14” long) on the center/left side of this idu. It appeared to be a yellow light oily substance and I immediately thought refrigerant leak. Then I thought the drain plug might be weeping since I swapped drain locations from this side to the right side. Or maybe fan bearing or fan motor oil (if there is such a thing?)

Are you sure this "oily substance" has leaked out of the unit? Maybe something got splashed on the wall?

 

[Jackfre]

Check to see if the wall is absolutely plumb. It is possible that if it is out of plumb water can collect and create your problem.

 

[SALIV8]

Are you sure this "oily substance" has leaked out of the unit? Maybe something got splashed on the wall?

Good point.

 

[SALIV8]

Check to see if the wall is absolutely plumb. It is possible that if it is out of plumb water can collect and create your problem.

I would guess its close but good idea I will check that.

 

[SALIV8]

Thanks for all the help everyone.

 

[Jackfre]

Another thing. It is possible that the mounting bracket has pulled away from the wall, tipping the evaporator and assisting the problem. When I installunits today I use toggles bolts in all four corners of the mounting bracket. With the line-set, power line and drain behind the unit, depending upon how you have installed it, when you try to close the unit onto the bracket, if not very securely mounted you and lever the top of the unit off the wall.
There are also interior conditions that can cause the unit to spit intermittently.

 

[hmbemis]

What sort of paint have you got on the walls? In my bathroom I'll develop oily looking drips like that on the walls if someone doesn't run the fan after showering. I assume maybe it's oil from the primer or something similar. I'm wondering if the unit is making the wall cold enough right underneath that some of the humidity in the air condenses and drips down a bit on the wall?

 

[Jackfre]

What sort of paint have you got on the walls? In my bathroom I'll develop oily looking drips like that on the walls if someone doesn't run the fan after showering. I assume maybe it's oil from the primer or something similar. I'm wondering if the unit is making the wall cold enough right underneath that some of the humidity in the air condenses and drips down a bit on the wall?

That is a good point and the insulation in the wall, or lack of, can absolutely be a factor in this situation.

 

[SALIV8]

The paint is a good benjamin moore latex. It didnt feel like water and left a weird kinda flaky clear gunk behind.

I suppose it could be condensation from wall but its odd that this is the first and only time its done this over 2 cooling seasons.

The wall is plumb and I also checked that nothing was pulling from the wall or that the bracket was loose.

The mystery continues. But nothing has dripped again, yet.

 

[SALIV8]

Thanks for the great ideas.

 

[SALIV8]

I just wanted to update this in case it helps anyone else.

I’ve had two more indoor units, on a completely separate multi head system do this same thing.

I have come to the conclusion it must be an anti corrosion oil spray the manufacturer has treated the wall mount steel frame with.

All units are still working correctly.