Mitsubishi Ductless Splits Mr. Slim

[dismas66]

Installed 2 Mitz. Ductless Split today,,,, after leak check, evauation..I asked the Electrician ..I hired........... If it was all set to fire up....

He says go ahead....turn the disconnect...on...
POP
He yells down ...standing in front of the Air Handler

He ended up smokin.. the board on the AH

Has Anyone had any experience with the wiring for these units...
and should I pay this hack...for destoying my payday ?

Now, I will need to contact the supply house on Monday..to replace the board...that he smoked

[baub]

What was wrong?

[dismas66]

Well,
He Failed to run a 3 wire...for the power supply///

L1 N L2

He ran ONLY 2 wires...
I may go with another electician...
to fix the problem
pissed m,e off !

[Freezeking2000]

The power supply for the indoor unit?

[Freezeking2000]

All you need is L1 and L2 and a ground.

The indoor unit gets power from the outdoor unit, maybe he wired 230V to the 12V dc controll going to the indoor unit.

If he did you are F***ed.


As the contractor before any switch get turned on you need to double check all wiring BEFORE you power it up.

[moose412000]

All you need is L1 and L2 and a ground.

The indoor unit gets power from the outdoor unit, maybe he wired 230V to the 12V dc controll going to the indoor unit.

If he did you are F***ed.


As the contractor before any switch get turned on you need to double check all wiring BEFORE you power it up.

Alot of times the outdoor unit is 120V and the electrician are used to using 240V outside
I have had this happen to me twice!!!!!!!!!!!!!!!!. Now I aways check before plugging in the disconnect. Go ahead and order a control board and if the transformer is not part of the board, order a transformer too.

Good Luck

[dismas66]

I am looking at the schematic for Mitz. MS 15 series
INDOOR UNIT

2 1 N L1
. . . .
. . . .
. . . .
. . . .
. . . .
2 1 N L1 L1 N L2 Ground
outdoor unit . . . .
power
supply

[dismas66]

The schematic failed to show up

there is a 12 V dc source

[dismas66]

12 V DC (polar)

[cjcargo]

After that happened did you ask the electrican if he could read?
The name plate shows correct voltage and the panel is clear as day how to wire the unit!
But who ever is the start up technician was should have check all that before power is energized to the unit.

[tinmantu]

After that happened did you ask the electrican if he could read?
The name plate shows correct voltage and the panel is clear as day how to wire the unit!
But who ever is the start up technician was should have check all that before power is energized to the unit.

Agreed!...We went out to install a 230 volt 3-phase at a plant, checked voltage at the contactor before startup 440 volts. Turns out the boss missed that on the label of the old condensor and ordered the wrong one. Glad voltage was checked before we fired it up. That comp. would have been screaming (for a few seconds anyway)

[Linmoth]

What model #'s are you installing?

Tom

[Freezeking2000]

I am looking at the schematic for Mitz. MS 15 series
INDOOR UNIT

2 1 N L1
. . . .
. . . .
. . . .
. . . .
. . . .
2 1 N L1 L1 N L2 Ground
outdoor unit . . . .
power
supply

MS-a09 or 12 cooling only unit has 230V to indoor and outdoor unit. I would not think a missing neutral would smoke it up. Look for the model #s in the instruction sheet so it will get properly connected.