Clean A/C Evaporator to Rid Mold/Midlew (Where/How to access A/C Evaporator Drain?)
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Clean A/C Evaporator to Rid Mold/Midlew (Where/How to access A/C Evaporator Drain?)
I plan on cleaning the A/C system to rid mildew/mold buildup.
I'm aware of a number of ways to:
The BG Frigi-Clean product requires disassembling the dash and drilling a hole into the evaporator housing to apply the foam.
The 1Z product you insert the included spray hose into the center air vent and hopefully gets close to the evaporator housing.
The Petro Chemical AC Cleaning System apparently connects to the Evaporator drain tube and the foam is applied that way. See this and this.
If I can find the Petro (Amrep) Chemical AC Refresher Kit, I think I'm gonna do that since it seems to be a good balance of ensuring you get into the evaporator housing but still is pretty straightforward and easy to do. Either way I'm going with a foam since it should be longer-lasting, and hopefully have a less intrusive smell than lysol.
Anybody know where and how to access the A/C Evaporator drain?
Any diagrams and/or brief write-ups would be extremely valuable and greatly appreciated!!!
I'm aware of a number of ways to:
- prevent buildup (turn off A/C a few minutes before shutting off engine or using Rest/Recirc after shutting off)
- spray lysol directly in climate intake/windshield cowl and/or vents
- 70% alcohol 30% water in mist bottle doing aforementioned.
- 1Z Clima-Cleaner
- BG Frigi-Clean (Evaporator Foam) & Frigi-Frest (Vent Spray)
- Petro Chemical AC Refresher Kit (trying to track down where to purchase)
The BG Frigi-Clean product requires disassembling the dash and drilling a hole into the evaporator housing to apply the foam.
The 1Z product you insert the included spray hose into the center air vent and hopefully gets close to the evaporator housing.
The Petro Chemical AC Cleaning System apparently connects to the Evaporator drain tube and the foam is applied that way. See this and this.
If I can find the Petro (Amrep) Chemical AC Refresher Kit, I think I'm gonna do that since it seems to be a good balance of ensuring you get into the evaporator housing but still is pretty straightforward and easy to do. Either way I'm going with a foam since it should be longer-lasting, and hopefully have a less intrusive smell than lysol.
Anybody know where and how to access the A/C Evaporator drain?
Any diagrams and/or brief write-ups would be extremely valuable and greatly appreciated!!!
Last edited by govertime; Jun 18, 2010 at 11:45 AM.
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BTW, seems the Petro Chemical product is also labeled by Amrep Chemicals and sold by various dealerships as a "A/C refresher kit" and contains isopropyl alcohol.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
See pipe at bottom of housing that drains through floor of car. You can check it for blockage from under the car where it drips
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
BTW - you can sort of access the evapourator from the Charcoal filter access area next to the blower. If you don't have Charcoal filters - some models have blanks inserted - you can remove these. Unfortunately some later models have this access blanked off. Depends on your car.
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Glyn you're the bees knees!
I suppose the evaporator is '4' in the first diagram.?? Then I guess '3' is the condenser.
I'm a bit hesitant since this diagram shows the flow of cold outside air being heated for the cabin.
I'll see if I can spot where under the car this drain is...hopefully I can get a pic to post.
Mods - This might be handy as a DIY sticky
I suppose the evaporator is '4' in the first diagram.?? Then I guess '3' is the condenser.
I'm a bit hesitant since this diagram shows the flow of cold outside air being heated for the cabin.
I'll see if I can spot where under the car this drain is...hopefully I can get a pic to post.
Mods - This might be handy as a DIY sticky
Last edited by govertime; Jun 18, 2010 at 08:40 PM.
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Joined: Jun 2008
Posts: 19,942
Likes: 192
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
RU seeing all three diagrams? I find the forum messes around.
3 is the evapourator in Diag 1 or 230 in Diag 2
1 in Diag 1 is the fresh air filter
3 is the evapourator in Diag 1 or 230 in Diag 2
1 in Diag 1 is the fresh air filter
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From: Richmond, VA Metro Area
2005 C230 Sport Sedan-6 Speed Manual
https://mbworld.org/forums/attachmen...y-a_c-odor.pdf
I used this document to identify the recommended location for drilling into the duct.
I’ve treated the system with several different products, but the smell returns. If you find a product that works permanently please share the information.
I used this document to identify the recommended location for drilling into the duct.
I’ve treated the system with several different products, but the smell returns. If you find a product that works permanently please share the information.
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From: New Orleans Area
2015 E400 Sedan
nothing works permanently since the evaporator will continue to have water condensing on it and dripping out the car.
Once off this wet evap is in a dark warm place which Bacteria loves....
Check your drain hose make sure it is really clear and allows all the water to drain out.
One way to prevent is: before you shut off your car - turn off AC and crank heater to dry evap... PIA to remember to do but keeps evap dry when not in use.
Once off this wet evap is in a dark warm place which Bacteria loves....
Check your drain hose make sure it is really clear and allows all the water to drain out.
One way to prevent is: before you shut off your car - turn off AC and crank heater to dry evap... PIA to remember to do but keeps evap dry when not in use.
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C55 AMG
Bumping an old thread... Thanks to @KevinH2000 for helping in my other thread. I have the dash apart for deep cleaning stubborn odor. This gives excellent access to AC blower motor and air inlet duct.
It appears air inlet duct leads straight to evaporator so will be applying foaming and self-rinsing cleaner. Home Depot has this:
https://www.homedepot.com/p/Simple-G...E&gclsrc=aw.ds
Simple Green product is inexpensive (unlike Toyota Refresh Kit) so multiple cans can be used on both evaporator and heater core. Toyota kit has aerosol can top with tube which can be used with Simple Green can.
I previously applied Toyota cleaner through rubber drain tubes that run from blend box to transmission tunnel which helped a lot. I had mistakenly identified these rubber tubes as access to evaporator. These tubes access heater core and bottom of blend box which is where water and mildew can accumulate. Applying cleaner through these tubes successfully removed smell and confirmed there is no blockage. If odor returns, drain tubes will be part of cleaning. On a side note, I think it is possible to rinse evaporator and heater core with distilled water.
Above photo shows passenger side. Still looking for the access hole drill point shown in the Service Bulletin. Mine car is not equipped with carbon cabin filter so white foam block is present. Looking for the alternate drill hole location.
It appears air inlet duct leads straight to evaporator so will be applying foaming and self-rinsing cleaner. Home Depot has this:
https://www.homedepot.com/p/Simple-G...E&gclsrc=aw.ds
Simple Green product is inexpensive (unlike Toyota Refresh Kit) so multiple cans can be used on both evaporator and heater core. Toyota kit has aerosol can top with tube which can be used with Simple Green can.
I previously applied Toyota cleaner through rubber drain tubes that run from blend box to transmission tunnel which helped a lot. I had mistakenly identified these rubber tubes as access to evaporator. These tubes access heater core and bottom of blend box which is where water and mildew can accumulate. Applying cleaner through these tubes successfully removed smell and confirmed there is no blockage. If odor returns, drain tubes will be part of cleaning. On a side note, I think it is possible to rinse evaporator and heater core with distilled water.
Above photo shows passenger side. Still looking for the access hole drill point shown in the Service Bulletin. Mine car is not equipped with carbon cabin filter so white foam block is present. Looking for the alternate drill hole location.
