Anyone clean their mini splits?

[jjrbus]

I DIY'ed 3 Daikin systems in my house and have been diligent about not just turning off mini, but leaving the fan on for some time to dry out coils before shutting down. I also clean filters on a regular basis. The coils look nice and clean with no noticeable mold or dirt.


But the blower, oh my, was shocked when I saw the build up on it. The unit has been in since Feb 2018 and runs most of the time here in Florida.


Searched the forum and found little on cleaning a mini or did I miss something? Looked at a bunch of You tube video's and a wide range of ways to go about it, from disassembling unit (which makes no sense to me) to buying a bag system to hang on wall and wash unit.



The owners manual only references cleaning the filters, which I do. I have only vacuumed them and never washed.



I read not to use cleaning agents on mini's then see lots of info on cleaning agents available. Which is right?



Any and all input, thoughts, ideas, suggestions, and wise cracks greatly appreciated. This is the 3rd forum I have posted this on with almost no response??


Daikin, 12K 15 Seer model # FTXN12NMVJU This is the first unit installed and is the workhorse of the 3 running most of the time, the other 2 are only used as needed so not so much build up on them yet

 

[Kaizen]

Yes should be cleaned every two or three years depending on amount of use. They have to be at least partially disassembled to get to the blower and drain pan. Mine was not cleaned as I didn’t know and the drain pan backed up and soaked the wall. Still on my to do list. Guessing it will take a few hours


Sent from my iPhone using Tapatalk

 

[346ci]

I've cleaned a few at work, getting the covers off was the hardest part. I used the foaming cleaner from lowes, tape a trash bag on the bottom to funnel the dirty water into a trash can. A garden hose with a small nozzle worked great.

https://www.lowes.com/pd/Yardsmith-1-Pattern-Nozzle/50328295

 

[wirt]

I learned the hard way about them, water ran down my garage wall all day before it was spotted and caused quite a bit of damage. Now I take mine apart every spring and completely clean it out. And I agree, getting the cover off is a pita.

 

[bonneyman]

It's one of those things that you forget about until it quits. Like the condenser coil on a refrigerator.

Which reminds me.....

 

[Jackfre]

Mini-splits are great, but..and you have discovered the ****. I do not put a "bag" under them but do tape up some 5 mil poly and run it into a garbage can. Have you inspected the evap coils on the back side? That is where they get dirty. About 40% of your coil surface falls to the back of the evaporator and that is where they get crapped up. I use a NuCalgon coil cleaner on mine and dilute it. I buy it at the local HVAC supply house. I have a pump sprayer for the blower wheel and coil. I carefully vacuum off the coil face and then wash it. You have to be careful here as you do not want to drive the dirt down into the coils and the fin spacing is very small. Wear a face shield if you do this. I have not been able to clean the wheel with a brush. Mass qty of needle spray with attendant back splash is the best way to do it, if you are unwilling, as I am, to remove the wheel. You will not believe the difference in operation once you get that wheel clean. I generally make sure my wife is going somewhere for a couple hours so I can do it without advice. You will want to clean the outdoor coils and fan blades as well. Here in CA it is so dry that I am always surprised when I see water coming out of the drain. In FL I would imagine constant drainage. Keep up with the cleaning or the organics will turn that evap into a mold petri dish.

 

[jjrbus]

Thanks for the responses, greatly appreciated.

In Florida some have to vacuum drain lines on a regular schedule to keep them from plugging up, some never have to. Guess it depends on length, slope etc.

I see no reason that a mini drain line would be any different and would benefit from vacuuming. Same as central air, pan to collect condensate and drain line. Start with a clean vacuum to see what comes out.

 

[MattT]

I've only thoroughly cleaned one once, after 3 years service. Already had it off the wall to move it so I did it outside. The blower wheel was disgusting but the coil still looked near new. I'm in a humid climate so the coil may be self washing. Coil also had some kind of blue coating on the fins which may prevent build up.

Based on how that unit looked I'm now just going to do drain pans and blower wheels annually. Plus continue washing the filters monthly. The condenser coils just get hosed out at the end of mowing season.

Regards cleaners you do have to be careful what kind you buy. Generally speaking evaporator coil cleaners are fairly mild but condenser cleaners can be very aggressive and acidic. And there are exceptions so research carefully before buying.

 

[jjrbus]

Thanks.

One tech mentioned that extending the filter cleaning keeps the unit cleaner, I guess drawing dirt through dirt is more efficient at cleaning.

Another tech says he uses hot water to clean the coils and not cleaners unless they are very dirty.

This is what we use when the coils are very dirty. Otherwise just plain hot water. Since ALL PM has stopped we have had to go to Simple Green when cleaning an indoor unit up. If we get one that is real bad we have used the NU-Calgon coil cleaner but thoroughly rinse with water afterwards. We have drain pans we put under the units so we get minimal water and dirt on floors and walls.

Ionic fluids are the worst enemy. Ionic fluids are electrolytes (conductive). This include salts, Coca-Cola, acids, alkalis, urine, etc. Acid and alkali eats aluminum on their own, but neutral ionic solutions attack aluminum when in contact with another metal even when it doesn't on its own. The issue is that many cleaners are conductive but don't tell you about it.

Sandwich a piece of paper towel wetted with Coke or salt water in between a piece of aluminum and copper. Don't let the two metals touch directly. Attach your multimeter in micro amp or mA mode. You'll probably get 1,000+ micro amps. In DC volt mode, you'll get something like 1.2v. That's 'letricity flowing generated by battery powered by aluminum getting consumed. I mention urine, because getting peed on by an animal is a fairly common cause of condenser coil fin damage.

It's hard to rinse out the solution that is wicked in between the coil and the fins and it will corrode the aluminum where it touches the copper which degrades the thermal conductivity between the two.

Wet the paper towel with something like Dawn + distilled water. Compare with wetting with a descaler. You'll see the difference. This is a easy enough test to do if you're unsure about the cleaner.

https://hvac-talk.com/vbb/showthread.php?1543721-Cleaning-mini-splits&highlight=mini+split+cleaning

 

[jjrbus]

mikep
mikep is offline Professional Member

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These micro channel coil manufacturers are very **** about using chemical coil cleaners. The issue is that the mc coils are highly susceptible to corrosion. It is not a matter of properly rinsing the coil after using a detergent; it is the initial contact with the detergent that causes the corrosion. Chlorinated rinse water may cause more corrosion to aluminum than the detergent. From a thread on Linkedin an engineer said that since mc coils lack the galvanic protection from the copper tubing as with conventional coils. Any highly charged detergents or chlorinated tap water may overtime induce stress cracking to the very structurally thin aluminum boundaries. We have been told to use only distilled water, no detergent, period.

 

[SALIV8]

Sheesh I hope I don't have to do the same thing. I keep an eye on my blower wheels and so so far so good. I don't mind a bit of buildup, (the same happens on a squirrel cage forced air blower which is never cleaned) but I hope this step I can skip.

We shall see. Mine have been in service for about a year maybe more.

I'm in a climate that has heating and cooling so maybe that will help? Have no idea.

But I do have the cleaning kit ready to go if needed.

 

[Jackfre]

Sheesh I hope I don't have to do the same thing. I keep an eye on my blower wheels and so so far so good. I don't mind a bit of buildup, (the same happens on a squirrel cage forced air blower which is never cleaned) but I hope this step I can skip.

We shall see. Mine have been in service for about a year maybe more.

I'm in a climate that has heating and cooling so maybe that will help? Have no idea.

But I do have the cleaning kit ready to go if needed.

You will have to clean the blower wheel. Just not yet

 

[Git]

I pull the blower wheel out of my two MrSlims annually, and they are filthy. It's really not that hard once you have done it a couple of times. I also use some 'no rinse' cleaner on the coils

https://www.amazon.com/dp/B00DM8KQ3I/?tag=atomicindus08-20

 

[PoorOwner]

Can you clean the blower wheel with a paint brush? Taking it off is a pita.

 

[SGKent]

For a couple years I used to travel for work. I'd have a hotel room for weeks on end. The first thing I would do on getting such a room, even a high end hotel, is pull the filter out of the AC system and wash it with soap and water then put it back. Then after disinfecting my hands, then I would call room service and have them clean the tub which would be black from all the debris that came off the filter. Mini-systems are usually over looked just about anywhere they are unless the owner has a diligent policy of cleaning the filters.

 

[jjrbus]

Had an interesting response on another forum. suggested using thin replacement filters on top of the mini filter. I am not recommending this, will be looking into it.

Need to figure how to measure air flow to see if it would restrict air flow too much.

example -https://www.amazon.com/True-Blue-Electrostatic-Hammock-4-Pack/dp/B00EZN1J9Y

 

[jjrbus]

Another tid bit comes up. My Daikins use a coating on the outside coils similar to blue fin technology to protect the coils. Called PE fin coil coating, no mention of it used on inside coils.

 

[PoorOwner]

if you cover the stock mesh with another filter and happen to decrease the flow too much the indoor coil may freeze.

 

[jjrbus]

Cleaned the shop vac today and while I was at it decided to vacuum the mini split drain the way I would central AC drain.

Put a white cloth on the vacuum hose to catch any gunk and almost nothing came out after leaving hooked up for 10 minutes, could clearly hear in the house so no it was working.

The EZ trap had quite a bit of gunk in it and not sure how to clean it. Soaking it in vinegar for now.

http://https://www.supplyhouse.com/EZ-Trap-83180-EZT-180-Waterless-In-Line-MiniTrap-without-Brush?gclid=Cj0KCQjwxMjnBRCtARIsAGwWnBPqYF9T2cuXZg6flj7cfM6-OLLOc0qp7PkfaLPgdvHTnajEUFQG1AEaAmKiEALw_wcB

 

[thammel]

I do both my mitsubishi mini splits today. One thing to note: If you remove the blower wheel to clean it, be very careful when reinstalling it that it spins freely and easily. I didn't check this on the first one and it made a racket when running. I quickly shut it off, pulled things apart again and moved it a bit so it spins freely now.

Tom

 

[jjrbus]

I do both my mitsubishi mini splits today. One thing to note: If you remove the blower wheel to clean it, be very careful when reinstalling it that it spins freely and easily. I didn't check this on the first one and it made a racket when running. I quickly shut it off, pulled things apart again and moved it a bit so it spins freely now.

Tom

Thanks for the input. I have read that the Mitsubishi wheels are easy to remove. Not sure on my Daikins, I am curious was the build up on the wheel soft an easy to remove or more of a caked on buildup?

 

[LS6 Tommy]

Cleaned the shop vac today and while I was at it decided to vacuum the mini split drain the way I would central AC drain.

Put a white cloth on the vacuum hose to catch any gunk and almost nothing came out after leaving hooked up for 10 minutes, could clearly hear in the house so no it was working.

The EZ trap had quite a bit of gunk in it and not sure how to clean it. Soaking it in vinegar for now.

http://https://www.supplyhouse.com/EZ-Trap-83180-EZT-180-Waterless-In-Line-MiniTrap-without-Brush?gclid=Cj0KCQjwxMjnBRCtARIsAGwWnBPqYF9T2cuXZg6flj7cfM6-OLLOc0qp7PkfaLPgdvHTnajEUFQG1AEaAmKiEALw_wcB

There shouldn't be a trap on a ductless mini split condensate line...

Tommy

 

[jjrbus]

Yes and no. The EZ is designed for mini's. Not being able to figure if they were required for code I installed them.

I am in SW Fl where any opening becomes housing for various types of critter. I opened the door on my old Toyota motorhome and a tree frog just about gave me a bowl movement! Using the area under the handle as his abode.

Left to my own devices or when the EZ fail I make a sock out of screen/mesh and attach it somehow.

 

[thammel]

Thanks for the input. I have read that the Mitsubishi wheels are easy to remove. Not sure on my Daikins, I am curious was the build up on the wheel soft an easy to remove or more of a caked on buildup?

I didn't have that much crud on my wheels; just hosed them off then blew them cry with compressed air.

Tom

 

[jjrbus]

Took the cover off the mini to take a look at what I am up against. There does not seem to be any easy way to get to the blower wheel on the Daikin, to clean with a brush or a vacuum. I am sure it could be disassembled and done, but looks like a bit too much work for regular maintenence.

It appears the flush with water and collect seems like the simple solution. I was concerned about getting water in the blower motor but with the amount of condensate in there the motor must be sealed of isolated?

The coils, especially the rear of the coils appear very clean. I could not actually see them and used a digital camera.

I see no build up of anything in the drain tray and no signs of mold. I did not put the AC in level but with a slight tilt towards the drain.

 

[jjrbus]

Here is what I come up with, I think but cannot confirm none on the manufacturers want coil cleaner used on evaporator (inside unit coils), so will be using hot water, will also be using distilled water.

Will use garden sprayer to apply water. I will buy a new dedicated one to avoid any contaminants.

Collecting the waste water has me a bit stymied. I have the cheap DNA and the though of buying disposable bags with some cords and sticks makes me cringe. So am looking for some input on that. It is time to paint and new carpet so if I make a mess experimenting this time is no big deal.

See any holes in this plan?

 

[SALIV8]

I have this kit in the box ready to go if needed...

https://www.speedclean.com/product/mini-split-bib-kit/

 

[jjrbus]

I always appreciate any and all input. But I have the cheap DNA gene. The kit is $89 for a loop of plastic and some string. I would chop off my left arm first! I could do the same thing with some old plastic blinds I have and some string.

I have 3 inside units to maintain so am thinking of cobbling something permanent together.

 

[PoorOwner]

When you spray the coils with water doesn’t the water drain off the condensate line?

Would the bib only for the blower?

 

[SouthLake]

I pull the blower wheel out of my two MrSlims annually, and they are filthy. It's really not that hard once you have done it a couple of times. I also use some 'no rinse' cleaner on the coils

https://www.amazon.com/dp/B00DM8KQ3I/?tag=atomicindus08-20

This ^^
I also have a mr. slim that’s about 5 years old. I clean it every two years. I clean the outdoor unit once every spring too. But that’s pretty easy
Pulling the blower wheel is really very easy. All the parts go together very easily. The biggest challenge I have is detaching the drip tray a little to make room for the wheel and to clean the tray.

I found this video helpful

 

[floridafarmer]

I'm in FL too and yesterday my Daikin indoor unit froze up for the first time since installing in late 2016. I clean the filters regularly and the outside unit as well. The fan looks like it has so much junk on it that it may be out of balance.. It would be great if it could be cleaned like in that video but I'm guessing I'll end up taking it apart to clean.
There is also some gunk in the water tray - I never looked at it that close.
I couldn't find a video on line showing the disassembly of a Daikin unit. Mine is a 15 seer 2 ton unit.
I also saw some posts about recall/rework on the bushings for the fan - they were going bad and getting out of balance.
If you take it apart - please consider a video or take lots of pictures!

 

[SouthLake]

are the Daikin units very different from the Mitsubishi Slims? i thought they would be pretty similar?

 

[jjrbus]

Thanks for the input always appreciated.

All mini's are similar. The blower motor in Daikin must be a different design as it does not look easy to disassemble. Being plastic I am not going to experiment with it unless I have no other choice.

I see no gunk build up in the tray, I did buy some tablets to try in the tray. https://www.amazon.com/gp/product/B073S8KDDR/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1

This is the only video I see on removing a Daikin blower wheel.

Maybe your manual is here?

https://www.daikinac.com/content/resources/manuals/service-manuals/

 

[floridafarmer]

All the AC companies are slammed to the wall here - so I'm still sitting here waiting for my service tech. So, I decided to try and clean it a bit so I used my compressor with a narrow nozzle blow tip and got up close on the blower fins - I'm amazed at the debris that came out. It filled a dust pan full but was very light weight. I gently blew thru the coils - just a little more dirt came out and wiped the plastic clean with a wet cloth.

The air volume now after cleaning is much stronger - all that build up on the fan fins must have really knocked down the efficiency. When my unit froze, I thought it might have been due to low freon but they also say that happens due to restricted air flow so maybe that's why it froze. I'll know when the tech checks the unit and freon charge. For now, really cold and running smooth.

 

[jjrbus]

Interesting, mine are in the house so a bit afraid of using compressed air.

With the size of the blower motor I think a large build up might weaken it or burn it out.

 

[jjrbus]

I picked up a small garden sprayer and some other things to clean the mini. Pulled the cover off and the sprayer will not reach the back of the coils. No big deal I am SHM, Super Handy Man! Warm up the tip of the sprayer and bend it to 90 degrees, and proceed to clean the coils. Not using any chemicals only hot distilled water. That part goes nicely and I am satisfied with the results.

Move on to do the fan blower and WHAT THE, with the lovers and baffles and such there is no way to spray the blower wheel! Check the net and smiling guys with bags under the unit and nothing that applies to mine. They seem to have removed parts, but no instructions and honest I do not want to start forcing/prying plastic parts made in China. SHM paid the price for that long time ago and learned his lesson after about the 20th time : )

I was shipped a defective evaporator unit and it was replaced and did not want the old one back. Never installed, I kept it in the attic. I got that out and took some pictures to post and more for me to have when I try to put it back together.

I will not comment alot on the pictures, hopefully they will speak for themselves. The rotating vane/louver needs to be bent to unhook it from the right side and then simply slides out.

This is for Daikin 15 Seer, FTX09NMJVU thru FTX24NMVJU, possibly other Daikins but I do not know. Hopes this helps someone.

 

[jjrbus]

There does not seem to be an obvious way to take this louver out, but think I can work around it? There are 3 snap tabs, but I do not want to force anything as I may need this for parts some day.

 

[jjrbus]

Update, garden sprayer is a dismal failure for cleaning blower wheel, not enough force! Had to use a small paint brush and keep brushing as I sprayed, time consuming and not easy.

Have played more with the extra unit and cannot see how to get last vanes out which would make the job much easier.

Looked over my extra Daikin wall unit and it is not going to be an easy or simple job to get out blower wheel. Daikin gets a big fat ZERO for design!

In the meantime will be looking for some type of pump setup for next job. I am sure pressure washer would make a mess in house so will not even try.

 

[PoorOwner]

if you just spray the coils with water do you need the bib/plastic under the unit?

 

[jjrbus]

Keep tinkering with this, still see no way to remove last set of vanes.

This is how to get blower wheel out, take 2 screws out and give it a good pull while holding the coil up in the air. This is on a bench, do not know how it would work out on the wall? There is a plastic tang in there but do not see how to free it other than a good yank. It seems like the blower is fastened to the motor and will not pull free? Daikin is going to get worse than zero for this setup.