Anyone ever install ductless air units?

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iwirehouses

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Just wondering if anyone ever installed these. 1 room ductless air conditoning. I am curious as to how it goes. I know a unit sits outside and a unit sits inside, both connected with a regirate line. My friend has a 20 amp 230v system for one room. The power feeds to the condensor outside, 2 hots and a ground, I assume from a disconnect with liquid tight flexible conduit. How would you get the wires back to the indoor unit though? It says it needs 6 wires - 1,2,3,L3,L4,Ground. I was thinking run liquid tight conduit back to the indoor unit and fish 6 wires, but there are no knockouts located anywhere at all on the inddor unit. I don't get it, I would love to know though.
 
I've wired many of these. Different manufacturers are different. All that I've seen have 240V condensing units. Some straight 240, others need neutral. Indoor fan unit generally 120v. Some you can take the 120v from anywhere (draws like 2 amps), and there is a low voltage connection between fan and condensing units. Basically like a ducted AC split system. Others require 4 - 6 wire line voltage connection from condensing unit to fan unit. Last year I showed up to wire 2 identical systems at a restaurant. I couldn't figure them out at first. Somehow the factory changed the units as one required 4 wires between units, and the other required 6. My problem was that I was only looking at one system at first. After some heavy duty head scratching, I figured I better look at the other system. Well the AC guy mixed up fan unit 1 with condensing unit 2 and vice versa. Apparantly factory changed things midstream. He had to pumpdown, recover, and swap condensor units, and wasn't real happy.
 
I had to wire one a couple months ago. It took a 20A, 240V circuit to the condenser. I then had to run three wires and a ground back to the fan. A1, A2 and A3. Between A1 and A2, they had 240V. Between A2 and A3 they had the 24V control.
 
It is a Bondaire unit. I know how to wire it, it needs straight 12/2 20 amp 230v to the condensor unit, then 6 lines to the indoor unit of 14ga. The problem is, there are no knockouts anywhere on the indoor unit. The outdoor unit is perfect, 2 1/2" knockouts, one in, one out. Where are the knockouts typically located on the indoor unit? This one has none. I figure they should put one on the metal mounting bracket that goes against the wall so you could drill through the wall and come right in with carflex, hiding it from view inside. Do you typically put disconnects on the outside of the building for these units? I was going to anyways. Also, would you use metallic liquid flex, or non metallic?
 
i have wired plenty of them --- and i believe they are all manufactured by the same company(made in china) but have different names on them. they come two piece. the evaporator(indoor ahu) basically hangs on the wall like a picture. it comes with a metal flat bracket that attaches to the wall surface and indicates where to drill the holes to the outside for the refrigerant lines and also the condensed water line. the evaporator has the refrigerant lines(charged) -- condensed water drain and electrical power and control cable connected and capped. they are ten feet long. but can be extended if necessary.... the outside condensor unit needs to be fed by it's required rated voltage --- 120 or 230 volts. the power/control sj cord connects and feeds the inside unit fan power and control. the charged refrigerant lines(ten feet long) connect to the condensor unit --- connect the liquid line and open the isolation valve to allow gas to purge the
evaporator of air as you connect the suction line. it has extra gas to allow for this..... there are no inside controls on the wall unit --- only remote control(hand held) --temp.-fan speed -- timer for on and off programing and control of the fan louvers which can be aimed or allowed to oscilate. the latest one i installed was high efficency and the are very quiet. many people are installing them as a secondary unit for power outages like hurricanes. we have installed many as a backup unit for data rooms and are as large as two tons of air. be careful when wiring these units the instructions and the connected or rated voltage required is poorly worded. i have one in my home and have had no problems -- it is four years old.....................
 
charlie tuna said:
the power/control sj cord connects and feeds the inside unit fan power and control.
Click to expand...

I have done a lot of these myself and have never seen one with SJ cord.

We have always had to provide the Field installed interconnecting conductors.

I have 36000 BTU Mitsubishi Mr Slim waiting to be installed at my house, it needs 3 conductors from inside unit to outdoor unit.
 
iwirehouses said:
Do you typically put disconnects on the outside of the building for these units? I was going to anyways. Also, would you use metallic liquid flex, or non metallic?
Click to expand...

I use Carflex to the unit. I also mount a bellbox on the unit and install a two-pole switch with a WP cover as my disconnect. You may also be required to drag two more conductors over and install a GFCI recept if there's not one within 25'.
 
Do you use car flex to get back to the indoor unit? I assume so, so do you use a second bell box as a junction? or just go straight through the wall to a knockout, then silicone the hole? Also, you had knockouts on your indoor unit? Where they on the mounting bracket? I'm thinking i may have to punch one in the metal mounting bracket.
 
iwire,
be careful about punching a hole in the metal bracket -- the space inside the evaporator is very tight --- everything must be in it's place or the evaporator will not fit properly tight to the wall surface. i have had units that i had to provide the control wires which i got them inside the wall and just tie rapped the sealtight to the incoming refrigerant lines and allowed the control wires to be open wired inside the evaporator........... these things are sooo quiet you don't even know they are operating!!!
 
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