Unclog A/C drain and remove musty smell easily

[tomcat1446]

Hi, I searched and couldn't find a how to on this so I figured i do a write-up to help anyone in the same situation.....

First thing I did was check the CX-5 service guide for unclogging procedure,
there was none, but there was a diagram of where the drain hose was,
it's behind the panel by the passenger left shin:

Next step was to remove the plastic panel, it is very easy, pops right off.

this is the rubber drain hose, you can see it's connected to a white plastic type barb connector:

Then I followed the drain exit point to under the car and determined where the white plastic barb connector comes out from underneath, I jacked up the car and crawled to the approximate location and to my disappointment the drain was unreachable, it's behind a heatshield that is not easily removed or bent out of the way.

So it was back to the top and try to unclog from inside the car,

make sure to clamp the rubber hose first before pulling the rubber hose out from the barb connector

make sure to get a bucket or container to catch the water:

Remove clamp and if there's no water, spray compressed air up hose and be prepared for water to flow out, clamp if you need to empty catch container

also, make sure to clear out any debris in the white barb connector:

Next, if you have musty mildew smell, spray some Kool-It (from Amazon) to get some foaming action into the evaporator coils to clean out any fungus or bacteria that has accumulated due to stagnant water.

Finally, just reassemble and reconnect the rubber hose to the barb, I added a zip tie just in case it clogs again, I wanted to make sure no water leaked thru the fitting.

Also, check your cabin filter do make sure it's clean, replace if it's dirty, can't believe dealers charge $90 for this, scum thieves, how do they sleep at night knowing they rip people off

 

[Kaps]

My toyota dealer charged me $20 for my corolla. But yes I will replace cabin filter on my own in My CX-5.

 

[Chris_Top_Her]

I've washed mine 3x now.

 

[yrwei52]

Very nice write-up and thanks! I was wondering is it a common problem for Mazda as I've seen the same problem happened on CX-9 which eventually sized the blower motor. My other cars have never had clogged A/C drain issue and have never washed or cleaned evaporator once.

 

[B-ham Gary]

I've gotten some water dropping down by the left foot, passenger side when I run my A/C on the hottest of days (it never really gets very hot around here). This has been the first summer with the car. Always garage kept and never had an issue with leaf or pine needle build-up.

I'll use this write-up to investigate the drain, so THANK-YOU!

Off to buy a can of compressed air...

 

[tomcat1446]

I've gotten some water dropping down by the left foot, passenger side when I run my A/C on the hottest of days (it never really gets very hot around here). This has been the first summer with the car. Always garage kept and never had an issue with leaf or pine needle build-up.

I'll use this write-up to investigate the drain, so THANK-YOU!

Off to buy a can of compressed air...

You're very welcome, glad I can help !!! let us know how it turns out.

 

[madar]

I've washed mine 3x now.

I thought you were joking about this. I actually washed mine with a nylon brush and high pressure water from a hose. Filter material is actually pretty tough stuff.

 

[PatrickGSR94]

One note about adding that zip tie... if it's clogged, the water wouldn't make it down to that zip tie anyway, right? Or if the white plastic piece is what's clogged, the water will eventually back up to the coils under the dash and probably overflow onto the carpet.

Do you think I could just use my garage air compressor with air blow tool instead of that canned air junk? I could turn the pressure down if high pressure might risk causing damage to something.

 

[blackcx5]

One note about adding that zip tie... if it's clogged, the water wouldn't make it down to that zip tie anyway, right? Or if the white plastic piece is what's clogged, the water will eventually back up to the coils under the dash and probably overflow onto the carpet.

Do you think I could just use my garage air compressor with air blow tool instead of that canned air junk? I could turn the pressure down if high pressure might risk causing damage to something.

I think tomcat only suggested zip tie in case the barb connection was not water tight,

i.e. if there's a clog in the future , water might start leaking from the tube / barb connector interface
so zip tying it would ensure carpet/cabin doesn't get wet from water coming from the black hose.


or if the black hose somehow unconnects itself via vibrations or bumps in the road, if it becomes loose any water from the AC will drip into the cabin. So the cable ties acts as 2 purposes, one to make sure the black hose is water tight to the white barb and to secure the hose to not come off from vibrations.



I'm sure you can use garage air compressor to dislodge any debris just turn down the pressure, you don't need that much to remove clog.

 

[blackcx5]

Tomcat1446 you are da man !!!

so after a long winter, started using the AC again for the first time and it smelled horrible !! at first, I thought it was just a cabin filter that need to be changed but after changing the cabin filter, the "locker-room" type foul smell was still there,

thanks to your post, I was able to get to the evap core and spray some mildew killing Kool It and its smells brand new again, no more foul smelling mildew , One suggestion though, I recommend straightening out the rubber hose as straight as possible to get to the evap core to get to the source of the smell, otherwise there's a 90 degree bend at the top of the rubber hose that the Kool-It straw can't get passed..

thanks bro, I love all your posts, you are a great contributor

this shows the long straw that comes with the Kool-It so it can get deep into the evap core





this was my cabin filter:


my engine filter still looked brand new @ 20K, so didn't bother changing it yet


just FYI guys , Amazon sells the combo cabin and engine filter for $17 shipped, PERFECT FIT ! I got the cabin filter with the activated carbon, no need to get expensive OEM, both parts are high qualilty, check the reviews

can't believe dealer charge $79 for a cabin filter install service !!!! what a scam !!

https://www.amazon.com/dp/ (commissions earned)

 

[PatrickGSR94]

Yeah the cabin filter is pretty much the easiest thing ever to change. $79 at a $tealership does indeed sound like a scam.

 

[yrwei52]

Tomcat1446 you are da man !!!
...
thanks bro, I love all your posts, you are a great contributor

Yep, tomcat1446 has been one of the best contributors for this forum! I like to read his many write-ups with detailed explanation and pictures!

 

[Kedis82ZE8]

I somehow missed this thread last fall. Nice writeup on clearing that pipe if it gets clogged.

 

[yrwei52]

... this was my cabin filter:


my engine filter still looked brand new @ 20K, so didn't bother changing it yet

The reason why your 20,000-mile cabin filter looks worse than your 20,000-mile engine air filter is because the cabin filter from factory is charcoal/carbon activated and looks little black and dirty even if it's brand new. If your cabin filter is non-charcoal white like those "genuine" Mazda cabin filter from US Mazda dealers, your two filters should look similar with the same mileage. Here is a picture showing the charcoal cabin filter I pulled out from a brand new 2016.5 CX-5 Touring in my dealer's showroom:

View attachment 216190

This's white non-charcoal Mazda genuine cabin filter (KD45-61-J6X) selling for as low as ~$17USD each on eBay:

I usually insist using OEM parts all the time but sometimes I do use good quality aftermarket air filters used for engine and cabin. The filter combo from Amazon suggested by blackcx5 looks like an excellent alternative for us!

 

[yrwei52]

Mazdda Cabin Filter Comparison

Went to Mazda dealer yesterday and took more pictures on 2016.5 CX-5's new charcoal cabin filter from factory, Mazda genuine non-charcoal cabin filter with P/N KD45-61-J6X, and Mazda Value Products non-charcoal cabin filter with P/N KD45-61-J6X-MV:

From the comparison picture shown above we can see those "genuine" Mazda cabin filters selling on the eBay are Value Products with white plastic frame instead of black. Value Products cabin filter is about $10 cheaper than Mazda Genuine Parts on list price.

 

[blackcx5]

thanks!! Yrwei, so they don't sell the OEM activated charcoal one that came with the car p/n MP111KD47 ?

on Amazon Genuine Mazda (KD45-61-J6X) does for $23

https://www.amazon.com/dp/ (commissions earned)

 

[yrwei52]

Mazdda Cabin Filter

thanks!! Yrwei, so they don't sell the OEM activated charcoal one that came with the car p/n MP111KD47 ?

on Amazon Genuine Mazda (KD45-61-J6X) does for $23

https://www.amazon.com/dp/ (commissions earned)

I don't think "MP111KD47" is a legit Mazda part numbrr but that is what was stamped on both plastic frames of factory charcoal filter and Genuine Parts OEM filter. Unfortunately Mazda North American Operations don't bring in charcoal filter installed in the factory to the US. Without activated charcoal/carbon I thought the genuine OEM cabin filter is definitely overpriced!

Worse, people see white non-charcoal Mazda genuine cabin filter and would think their factory black charcoal filter is too dirty and make unnecessary replacement with a inferior non-charcoal OEM filter. What a waste!

 

[Tom 6-6]

I got the non oem filters on Amazon in February . Very nice and the cabin is charcoal coated. I could not find the cabin locally. Will buy these again.

 

[tomcat1446]

this shows the long straw that comes with the Kool-It so it can get deep into the evap core

thx for the great tip blackcx5, this gave me an idea to get deeper into the evap coils to really clean out the mildew, I found it difficult to try to straighten out the rubber hose and still try to feed the Kool-It tube thru the hole at the same time, I figured out the top of the rubber tube is also removable and that made it really easy to feed the kool-it tube, just thought I share this..... thx









Also, found a great video showing what to do if your passenger side starts getting wet from condensation water.....

credit goes to "kogut1974chicago" for making the video :

just FYI, if your rubber hose needs to be replaced, p/n is KD4561526

 

[agog]

That is exactly I missed and faced it. I put Kool-it from the lower end and the tube didn't go beyond the upper joint and almost all kool-it came back, wasted it!
I was also wondering if I could remove it from top, will try it next but probably need a new kool-it can.