Attempting to remove part of the A/C. MC9

[richard5933]

JIm, the reason you need the good technician, and by "good" i mean bus experienced, is to sort out the rest of that (profanity deleted) system without bankrupting you....

Buswarrior

Yeah - maintaining the OTR a/c system is not for the faint of heart (or wallet).

I like Jim's idea of using the OEM air handler and evaporator. Might be an engineering challenge to set up, but that air handler will get the cooled air throughout the entire bus. Not sure how up to the challenge that mini-split compressor will be though.

[TheHeavenlyChillbillies]

I keyed in on a great point mentioned, and thats disconnecting the electrics to the big motors your disconnecting. In the 9, mine is the first bay driver side above in a flip down compartment, housing the solenoids.

Floyd

Where does that fan wire terminate?  I was in that flip down compartment and tested for continuity from the outer compartment and couldn't seem to find it.

Everything else has already been removed.  I live in the bus for most of the the year...and I only travel maybe 20-30 actual days.  Having effecient (solar powered) heating and cooling while the engine is not running is the priority and I'm putting the indoor unit towards the front so it should be better than the fan/window combo I'm currently using.

Going to get the solar panels Monday to make it all work. 8x240 watt to go with the 530 AH bank I already have.

So by Tuesday I should have totally off grid A/C ☺️


If someone can tell me what the relay is labeled, that terminates the fan wire, I'd appreciate it .

[buswarrior]

Big red button in roof of first bay, street side.

Inch around, out in plain sight, points sideways.

No books here to refer to...

Which model of bus are you working?

Happy coaching!
Buswarrior

[TheHeavenlyChillbillies]

84 MCI MC9

There are three red button/breakers.  Labeled in the attached schematic.

[TheHeavenlyChillbillies]

Completed project:

[buswarrior]

Excellent report!

What unit did you use? Specs? Source?

Busnuts gotta copy...

Happy coaching!
Buswarrior

[TheHeavenlyChillbillies]

Enso 12,000 BTU Mini Split, 110v

$520 Delivered on eBay...came in 3 days.

Took me 3 or 4 hours to get the old stuff out...probably 4 or 5 to install.

Works significantly better than my roof top with almost no noise.  Pulls 12 amps when inverter is ramping up and then drops to about 3-4.  (Peaks at about 35 amps DC @ 24v)


Very happy with the move.  I'm picking up 8x240 watt solar panels on Monday which should be significant to run the A/C with charging amps to spare.  The panels and will have the added bonus of blocking a good chunk of sun from hitting the roof

[TheHeavenlyChillbillies]

Follow up.
The difference is amazing with the mini split compared to the rooftop.  Obviously the rooftop wasn't running at 100% but it was still blowing cold air.  Today it was 87 and sunny in Florida and the bus gets direct sun exposure for 5 to 6 hours on one side, and it's black.

The new air conditioner was able to keep the bus at 65 degrees without sectioning a third of the bus off like we usually did.  Further more the inside roof is substantially cooler.  My guess is it's because the mini split pulls air in from the top...and it's a few inches from the ceiling. I'd also imagine that since the evaporator is in the shade, as opposed to cooking in the sun, it has less work to do.

Lastly...I plugged the mini split in to my inverter/battery bank and it ran great.  My rooftop couldn't start off of my current inverter.  So I can run the mini split while driving now.  Hooray!  Very happy with my purchase.

[DoubleEagle]

I hope you have good luck with the Enso, not everybody does. Brands that cost a little more like Senville or Pioneer have higher success rates. You vacuumed the lines before the freon was installed? If not, there will be trouble at some point. The heating portion of the unit will not work below a certain temperature (usually 30-40 degrees F). Some people think that there is something wrong with the unit when it all of a sudden stops producing heat. How long of a copper line was provided with the unit? Some only come with 10 ft. of line, which would make it difficult to install, depending on where the components are mounted in the baggage bays.

[TheHeavenlyChillbillies]

note: if you buy inverter type your split will start and run at same amps.

That's not what my multimeter is saying . From what I've researched and experienced that's not correct.  It's the specific reason I bought this type of A/C.

I'm regards to quality, longevity, etc...  They were 11 foot lines...there was a few feet extra and it's already installed, the lines came capped, and for $500 it was good for a trial run...if I get a few years out of it I'll be delighted.