A/C Evaporator Cleaning for smelly A/C

[uparmoredyotas]

Resurrection.....

So i drilled a hole by the drivers side of the evaporator and emptied a bottle of foam no rinse evap cleaner onto the evaporator, the problem is it is not draining out of the vehicle, most of it came out the vents of the bottom of the hvac unit (the ones that go through the center console and point at the rear seats)

I still do not see any type of drain on the unit, and regardless of cleaning the evap and mold i need a functioning drain right? Can someone shed some light on how/where the drain is on this vehicle???

 

[Battleship]

FWIW- I have always made a habit of shutting off the AC and letting the fan run for at least the last minute or two before shutting the car down.(sp?).

I do this too. Is there a way on the 200 to make toggling the compressor easier - I have to select Climate, then one sub-screen down to get to the button on the MFD that turns it off. Is that how you do it? Worst feature on the 100 and 200 series is the MFD.

So i drilled a hole by the drivers side of the evaporator

Sorry I don't have much info for you, I haven't looked for the drain. But I think with the aerosol foam type cleaners you should drill the hole between the fan and the evaporator so that the foam gets blown through the coils. Couldn't tell what you meant by drivers side. Good luck.

 

[2021 LC200]

As part of keeping the AC clean of mold and the drain functional, I am looking at cleaning the evaporator coil and have read up with interest this thread. I like the idea of dropping the fan and getting access to the evaporator from the side. I may try that approach

Alternatively I am considering removing a center vent (or both) and put a hose to foam via the top. Below some info I have found which suggests that maybe feasible. Has anybody tried it this way? Any thoughts?

1) Removing the vents
Per videos of opening up the dash seems to be 1) pop off the speaker grill and set aside and then 2) from the top unclip each vent and pull them out. Next you have access to the ducts (recessed about 6 inch or so) which you probably can reach with a flexible hose and access the evaporator box and coil from the top (going in turning left and then down...).

2) Evaporator Access
Looks like the inner two "ports" are the once ducted to the center vents and provide access from the top, with the ability to foam the evaporator using a small diameter flexible hose.

Next two snapshots are from a video removing the entire dash and evaporator box.

 

[2021 LC200]

Looks like those ports in the evaporator box have flaps (black) which need to be in the open position for this. I would think they are open on my vehicle as i always get AC out of the center vents in auto mode. Otherwise I may manually control and put the fan in the lowest position. It can also be that the dials at the vent close of these ducts and there are no flaps in the evaporator box at the position shown. Anybody who knows?

 

[bloc]

I once had a car where the open cell foam sheet from the blend doors was breaking down and slowly raining out from the AC vents, staining everything it touched.

After that experience there is absolutely no way I’d consider putting any chemical down through the vents that had any chance of starting that process in my 200.

 

[2021 LC200]

I once had a car where the open cell foam sheet from the blend doors was breaking down and slowly raining out from the AC vents, staining everything it touched.

After that experience there is absolutely no way I’d consider putting any chemical down through the vents that had any chance of starting that process in my 200.

Interesting thought. Toyota sells foam to be applied to the evaporator box. Letting it sit for a while seems good idea, so it breaks down and runs away.

Have you tried to clean your evap in another way?

 

[pvchaitanya]

You are just over complicating it for the front AC evaporator cleaning. Use the toyota evap hvac cleaning foam. Put the foam through the hvac filter in the glove box and direct it on to the evap coils. I put a video cam in there an saw it is right there, empty one can, and do another one through the front two vents beside the center screen. Do not run AC immediately, after 5 mins , run the AC and you will see all the foamy water empty out under the truck (in the middle).

I tried using other brand HVAC coil cleaners which require no rinse, but they do not melt quick enough.

Front one is easy to do, if anyone figured where to spray this foam for the rear AC unit, let me know.

 

[2021 LC200]

You are just over complicating it for the front AC evaporator cleaning. Use the toyota evap hvac cleaning foam. Put the foam through the hvac filter in the glove box and direct it on to the evap coils. I put a video cam in there an saw it is right there, empty one can, and do another one through the front two vents beside the center screen. Do not run AC immediately, after 5 mins , run the AC and you will see all the foamy water empty out under the truck (in the middle).

I tried using other brand HVAC coil cleaners which require no rinse, but they do not melt quick enough.

Front one is easy to do, if anyone figured where to spray this foam for the rear AC unit, let me know.

Thanks much for this. I wondered about doing it that way.

You have to get the hose through the fan to get in the evaporator box, right?

Any risk of damaging or bending the fan blades so it is out of balance thereafter? Or just with a bit of care it works out fine?

 

[2021 LC200]

if anyone figured where to spray this foam for the rear AC unit, let me know.

I understand you can apply foam through the rear evaporator drain which is accessible behind the bumper, by removing the mudflap and adjacent panel driver side.

Plastic black panel to be removed for access to the drain (picture of another LC200). Maybe able to leave the mudflap on.

 

[pvchaitanya]

Thanks much for this. I wondered about doing it that way.

You have to get the hose through the fan to get in the evaporator box, right?

Any risk of damaging or bending the fan blades so it is out of balance thereafter? Or just with a bit of care it works out fine?

there is no need to bend or put pressure on any fan blade, you can see the opening to left and send the pipe into that area and spray. Yes you may need to spin the fan so the pipe can go into that area between fan blades. If you want to be sure, buy a cheap usb cam on amazon which can be sent into tight spaces, you can see if the spray nozzle is in the correct area.

 

[bloc]

Have you tried to clean your evap in another way?

Nope, the cabin filter works in both recirc and fresh air modes, and in over 100k miles I haven’t had any smells to worry about, so I haven’t felt the need.

Dealer service departments also sell Toyota-branded wiper blades that are not produced by Toyota or near the quality of the originals on your truck. Them selling stuff like evap core cleaners doesn’t mean the engineers that designed the vehicle would be happy about it going through the blend door system.

 

[2021 LC200]

Thanks all for the thoughts and input. I am going to try to apply foam via the cabin filter/fan housing as preventive maintenance (manage mold, ensure drain stays open) probably when fall sets in and outside temps here in Houston become more reasonable.

Will also try the rear via the drain.

Once I do I will keep you all posted.