2nd Gen Non-Engine/Transmission HVAC Evaporator Cleaning

[Sasquatch]

I've read several nightmare stories posted by guys who've had AC problems that started with a "musty" smell, and ended up with the removal/replacement of the evaporator coil, which is expensive as hell, and a very time consuming, labor intensive job.



I wonder if there would be a way to periodically introduce an aerosol cleaning solution into the dash, air returns, and maintain a relatively clean, efficient coil in the process?



There are all sorts of specialty cleaning solutions available in aerosol form; there's even one designed to be sprayed on chandeliers, which removes the dirt, and dries residue-free.



Everyone who's sprayed "contact cleaner" on a balky TPS knows what I'm talking about.



I've read several threads which mention the difficulty of removing the evaporator coil, either to clean or replace it, and I wonder if a far easier remedy might be effective—particularly if done as a form of routine, scheduled maintenance.



What I had in mind was turning the AC on, blocking the dash, return-air vents—except for the one that's directly over the evaporator coil—setting the fan speed on "high," and gradually spraying into the remaining return vent a can of evaporative cleaner.



I figure, "It couldn't hurt," because my AC performance has deteriorated noticeably; recharging the system doesn't help, and I, too, am beginning to smell that tell-tale mustiness.



Anybody have any thoughts?

 

[illflem]

Best preventive maintenance is to install a cab fresh filter

 

[Sasquatch]

Illflem:



I take it, then, you're not enthusiastic about the after-the-fact, "spray and pray" approach?

 

[R.ebel]

Musty smell

See TSB 24-11-97

 

[Wiredawg]

Liquid Lysol and Warm water

Sprays cover up the scent for a while, but don't correct real problem of leaves, dust and mold covering evaporator. There is a 3/4" long drain tube from the evaporator located on right side of firewall. I installed a 2 foot heater hose (5/8" I think) and a hose clamp. I take about a quart of warm water, add a couple of tablespoons of the liquid Lysol, turn drain hose up and pour contents into hose. Leave sit overnight. Drain. You'll see a crud coming out of drain. Truck will smell like a hospital for a while, but better than musty smell. May have to repeat.



Prevention is buy vent filter from Genos. Recommend buying stainless steel screws to replace the ones in the filter kit. I'm replacing mine as soon as we get warm weather.



Hope this helps, Wiredawg

 

[Sasquatch]

Wiredog—



Sounds like an evaporator enema, bro'.



The only thing I wonder about, with your approach, is how the cleaning solution gets to all the surfaces of the evaporator coil, itself, especially the top, since the coil is vertically oriented?



Unless the evaporator is encased in a watertight compartment, and flooding its cavity with a warm detergent solution will ensure complete immersion, I don't see how the lysol enema would solve the underlying problem of clogged evaporator coil fins.



Also, it's hard to imagine that one quart of liquid would accomplish the desired end. Finally, I think I'd use a solution that included clorox or some similar mildicide, would be good, as opposed to using lysol, which may disinfect, but won't remove mold without heavy duty elbow grease.



When we clean regular home AC condensing units, we spray them with a garden sprayer containing an emulsion of water, bleach, and "M1 Housewash. " We let the solution sit on the fins for about an hour, then flush with clean water and a hose-end sprayer. The result is a "like-new" condensing unit, with no trace of dirt remaining in the fins.



The aerosol evaporator cleaner makes more sense to me, intuitively, because it's logical that airborne containments would be susceptible to cleaning by airborne "decontaminents. "



In any case, I very much appreciate your thoughtful reply, buddy, and will try your approach, too. I'm thinking that a combination of both techniques might be the best way to approach this. Perform the TSB with the evaporator cleaner provided by MOPAR to get into the 'innards' of the cooling fins, and then follow up with the solution flush in order to remove heavier debris from the collection pan, hoses, etc.



Thanks, too, illflem and rebel for your helpful input.

 

[Wiredawg]

Two Quarts Blows Bubbles!

Sasquatch:



I've never seen one of our evaperators out of the truck, but I think my system works. I left out of my previous post the problem had been much worse on my former 2500 and I put two quarts in. Decided it would work better driving it for a day. Had fluid in the passenger compartment and was blowing Lysol bubbles thru the blower. Can't say which was worse for sure: The smell of mold or my trucking ODing on Lysol.



Interesting sidnote: My wife parks her 96 gasser Ram truck under the trees (we live in a forest) and never has any problems. My former 2500 and my 3500 after only a month were mold factories. Fixed problem in both with this solution and finally on the 3500 with the vent filters.



Final note: AMWAY sells a great disenfectant/germicidal that smells really good as opposed to Lysol liquid, which smells real mediciney. No, I'm not associated with AMWAY, but that is a great product.



Wiredawg

 

[1tuffram]

A question for those of you with the cab filter from Geno's. How often do you replace the filter element??

 

[illflem]

I would think you only need to replace it if it falls apart, it can be cleaned with water.

 

[Sasquatch]

I've read a lot of owner testimony that 'debris' accumulates on and around the coil, in addition to the normal, to-be-expected, airborne dust and contaminants that would be removed by the Geno's cab-fresh air filter.



If the system's return-air vents are the only source of contamination, I'm wondering how large debris such as leaves, etc. , are introduced, in the first place. If there is another way for crap as large as leaves to be sucked in, then it seems like the cab-fresh filter might be a case of "locking the barn after the horses have run off. "



How would anything as large as leaves get into the system in the first place—how can that be prevented—and how does the cab-fresh filter address that sort of problem, or keep the coil clean, if there's another way for contaminants to be drawn in.

 

[Broullire]

Sasquatch,

Did you ever get any answersw to this question?

 

[Canadian Cummins]

No Amount of spray wuld get rid of this



This is what my evap looked like last spring (06), I had a leak probably due to the crud & muck but no bad smell.

Mind you it would be frozen for the winter here in the great white north!!!

Just a couple of picks of when my local AC guy changed the evap, took all day 2 guys but he only charged me book rate so I was pleased, but still expensive.

I took about 42 photos while they did the work, they thought I was nuts

Any way I you guys need some photos PM me and I will zip them in a e-mail.

CC

 

[WDixon27]

heres a post where i suggested checking it and the blower through the blower hole for trash build up https://www.turbodieselregister.com...something-do-clean-out-your-blower-motor.html i blew mine fairly clean with just a hose, you can get your hand all over the intake side of the evap, if you have a mold problem theres probably lotsa crap in there for it to grow from and hold the moisture

hmmm, just noticed how old this thread is, oh well