Cleaning Ductless Heat Pump

RWebb · RWebb's Garage

Daikin mini-split - it's 7 years old and seems to need cleaning all the damn time - manuals says after several seasons, but it's more like every 6 months

I'm not talking about the $150 cleaning (where some kid knocks the dirt off of the plastic filter)

I'm talking about the squirrel cage blower fan which is full of crud and very hard to see, much less get at. It costs $350 for a kid to spray foam in there, then catch the drips in a funnel shaped plastic bag that leads to his 5 gal. pail.

Anybody know how to really clean these?

biosurfer1 · 09-22-2020, 03:45 PM

Compressed air wouldn't work? I'm sure it would create a bit of a mess, but I would think a strategically placed vacuum could catch most of it.

Roswell · 09-23-2020, 08:56 AM

same problem with the Mitsubishi. It takes the tech longer to take the unit apart than to clean it. So far it has been a once a year cost at $330.

RWebb · RWebb's Garage

Compressed air would work on the dust - and create a huge mess even with a shop vac

won't work on the 'crud'

peppy · 09-23-2020, 11:22 AM

Crap I didn't know I needed to to this, and there is no way I'm paying $300 to have it done. Mine is 2 years old and does have mildew on the louvers that I have wiped down with dish soap and bleach water. That seems to take care of it for a few months. I have never taken it apart.

peppy · 09-23-2020, 11:38 AM

RWebb · RWebb's Garage

Well, the Daikin manual says you may need to clean it after a "few seasons." Mine won't last that long.

None of the kids* who have come out to clean it have taken it apart either. They shoot some sort of foam or something else in there, then rinse it off - as in the Fujitsu video peppy posted. Maybe that isn't effective?

There must be instructions on cleaning in some manual for HVAC "expurts" that Daikon puts out but I haven't seen it anywhere.

* it seems there is a real shortage of people in this area, like the rest of the trades

peppy · 09-23-2020, 12:13 PM

Spraying coil cleaner with a garden sprayer and then rinsing with water using the same garden sprayer should do most of it. That is how I clean evaporators in walk in coolers. The mini split should have a drain that can handle the liquid.
I may give this a go this weekend and see how it goes. Mine is in a kitchen so I'm not worried about water on the floor. I will try and drape with plastic.

RWebb · RWebb's Garage

I'm pretty sure those ready-made plastic funnels are sold somewhere...

Roswell · 09-23-2020, 12:19 PM

The problem is cleaning the squirrel cage blower fan. It fills up with lint? and greatly reduces the efficiency of the fan, to the point the blower will put out no air flow.

peppy · 09-25-2020, 08:33 AM

Quote:

Originally Posted by RWebb

I'm pretty sure those ready-made plastic funnels are sold somewhere...

I found this one from supply house.

https://www.supplyhouse.com/Nu-Calgon-4150-01-Clean-Guard-Mini-Split-Maintenance-Bag

peppy · 09-25-2020, 08:35 AM

https://www.amazon.com/Split-Conditioning-Service-Mounted-Cleaning/dp/B087639WRK/ref=sr_1_6?crid=W4WSZFQ068ZN&dchild=1&keywords=mini+split+cleaning+kit&qid=1601051660&sprefix=mini+split+c%2Caps%2C232&sr=8-6
This one is cheaper

peppy · 11-23-2020, 04:06 PM

I cleaned ours a few weeks ago using the drape from amazon and a pump up sprayer from harbor freight. I used a coil cleaner and rinsed it with water, then used a mold/mildew tile spray for the plastic parts behind the blower wheel. I did not take the blower wheel out, I just removed the covers. It was pretty dirty, but came clean in about 1.5 hours.

red-beard · red-beard's Garage

I will never complain about replacing AC system whole house (4" thick) filters again.

peppy · 11-23-2020, 05:10 PM

If I had known this is what was required I would never have agreed to put one in.

dan79brooklyn · 11-23-2020, 09:45 PM

Yep. I live in Japan. We have 4 split system AC units all Daikin. The big one in the living room stopped blowing cold air this summer. I could see that the fan was covered in dusty grime. We had a technician come out and he confirmed my suspicion that it needed to be cleaned. He was nice enough to show me how to clean it and didn’t charge us anything. Basically take off all the plastic covers to expose the long horizontal fan and go in there blade by blade with small brushes/toothbrush. It will take a while and make a mess. Wear a mask and keep a vacuum going underneath you. But 30-40 minutes later you’ll be done and it’ll blow cold and clean again.

billybek · billybek's Garage

Do you leave the fan on continuous operation or does it just cycle on with a call for cooling or heating?
Since you don't have a central system filtering the air, how about a stand alone hepa filter in the house near the head unit? Would at least knock some of the dust out of the air and maybe prolong the run time between cleanings.

red-beard · red-beard's Garage

Sounds like a missing feature. They need a filter on the air handler/evaporator

billybek · billybek's Garage

Quote:

Originally Posted by red-beard

Sounds like a missing feature. They need a filter on the air handler/evaporator

There is a filter... It is sized to stop small rocks.

RWebb · RWebb's Garage

this is a Daikon, aka "lousey radish" heat pump

the squirrel cage blower collects dust and MOLD

it cannot be removed w/out removing the entire unit from the wall

!@#$%^&*()_(*&^%$#@!#$%^&*