Drillling HVAC box to clean evap coil

I've been dealing with a stinky AC since I bought this truck. Normally I run a can of evap cleaner through and it solves the problem for a few weeks/months. I've found it is better to apply it from inside of the HVAC box directly to the evap core than to go up the evap drain tube. Instead of pulling the blower fan every time I want to drill a hole in the HVAC box so I can squirt a can in and be done in 5 minutes since it seems I need to do this so often.



Has anyone done this? I'm looking for the ideal spot to drill a 1/4" hole and then plug it up with a rubber stopper so I can reuse it next time around.

 

Pulled out my endoscope and did some playing around. Originally I was thinking here by the blower resistor but I'm not too sure now


I used some chicken wire coiled up and a magnet to confirm exactly what is on the other side of that spot


This would in theory work but I feel like it would dump a lot of the contents of the evap cleaner towards the blower fan. The instructions for BG Frigi-clean instructs you to drill into the HVAC box and empty the can while the blower fan is on, probably for this reason? I think the best spot would be on the back side of this box more towards the driver side but it's impossible to get to. Or maybe I could just use that hole but make sure I stick the spray tube as far in as I can before emptying it.

Another idea was to maybe do it on the drivers side of the evap but I couldn't oriented myself like I did with the resistor.

 

Any location update to drill a hole to effectively clean HVAC box? Thanks

 

I still haven't pulled the trigger on this, I like the spot I marked in my post but you'll need to pull the blower and stuff rags in its place so any cleaning foam doesn't come back up the hvac ducting.

 

Mike,Dropped blower motor. Hand cleaned black grime off of each fan blade and inside lower main case. New cabin filter for now. I like your idea and will try to cap duct to inject foam cleaner.

Caribe, thanks for exploded view. Looks like need to take off cover to heater core and clean that separately.

 

Let me guess y’all don’t turn the ac off and turn the blend door to fresh and run the fan on high for a couple minutes before turning off the truck.

 

Is this a trick question? Is the answer, ask me how I know?

 

I did this a few years ago, tapped in front of the heater so I could hit both cores. If I remember tomorrow i'll take a pic. Used Frigi-clean as well, good stuff!

 

Please do, thanks. What was needed to tap hole? I wonder if a soldering iron would make an entry and drain hole?

 

Use a drill bit, thats the only proper way for a nice round hole. I don't remember what size bit I used but I just eyeballed it, not too big not too small. One end of the brass adapter included in the kit has course threads on it that self tap the hole and actually do a pretty nice job of it, for extra insurance I did coat the threads with a little epoxy before snugging it down. I'll have a pic for you by tonight!

 

Mine stunk years ago. I took out the cabin air filter, turned the A/C on high and while running, sprayed Lysol Nutra Air into the filter opening for 30 or so seconds. Then, I closed the door of my truck and let it run for about five minutes.
I had to clean my windshield a few times afterwards in the following months, but it really helped. That's been a couple of years now and the stink hasn't come back.
I would recommend doing this on a hot, humid day, so you get some 'rinsing' effect of the cold evaporator coil pulling some moisture out of the ambient air. I did it on recirculate.

 

This is useful, do you know if you can take the heatercore cover off without pulling the dash, just for inspection? Both my heat and AC smell nasty and I've been dealing with this for years. The original owner must've done something special. Next stop is to try ozone treating my system.

 

Dash pull is not an option, it's necessary...

 

This is where I ended up installing my port. I looked at as many pictures as I could but at the end of the day I just took a educated guess. I will say though that after spraying in the Frigi-Clean in per the instructions I had foam cleaner spitting out of my ac vents in the cab as well as coming out of my A/C drain hose, felt confident is worked its way around the whole system. Can't recommend the stuff enough. (please ignore that oem nasty tape, I don't know what that stuff is made of but good lord it's on there!