Electrical and/or HVAC question

SEE ARE125
Edited Date/Time 2/12/2022 10:53pm
Just installed a 240v 18k BTU ductless mini split on my detached garage. I have power to the AC disconnect box, but on the load wires leaving the disconnect box there’s no power. The disconnect switch is installed in the ON position, I’ve triple checked that. According to the manual, the mini split is 20amps, the disconnect I installed is 30amp(recommended by Home Depot), and the breaker for the 240v circuit in my breaker box has a double post 20amp breaker for 40amp total. Any ideas why I’m not getting power to the load wires after the AC disconnect? Sorry if this is a stupid question, but I’m a bit lost right now. Could the disconnect box be bad? Thanks for any help.
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sumdood
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sumdood 2/12/2022 12:47pm
2/12/2022 12:47pm
Did any of it come pre wired ? Maybe a wire not stripped or only partially stripped ? Did you try the off position just for the fuck of it ?
sumdood
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sumdood 2/12/2022 12:49pm
2/12/2022 12:49pm
Are there fuses in the disconnect box somewhere , the power has to be stopping somewhere
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SEE ARE125 2/12/2022 12:56pm
2/12/2022 12:56pm Edited Date/Time 2/12/2022 12:58pm
I bought a pre-wired AC whip, but I stripped all the wires myself, all connections are tight. I did try putting the disconnect in the OFF position and still nothing. lol The disconnect box Home Depot recommended is this one. https://www.homedepot.com/p/GE-30-Amp-120-240-Volt-240-Watt-Fused-AC-Di…

It says it’s a fused disconnect, but I didn’t see any fuses?
HD1200
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HD1200 2/12/2022 1:01pm
2/12/2022 1:01pm Edited Date/Time 2/12/2022 1:02pm
Did you turn on the breaker in the panel?

The Shop

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SEE ARE125 2/12/2022 1:05pm
2/12/2022 1:05pm
It’s not pretty, but here’s what we’re working with. I know white is used for neutral, but that’s the original wiring from 1995, and white was used for the 2nd hot wire. From my understanding it’s supposed to be red now, but I’m not running new wiring just to change colors.


Both the black and white coming in the back of the disconnect box have power, the black and red running out the bottom of the disconnect box have no power.
SEE ARE125 2/12/2022 1:07pm
2/12/2022 1:07pm
HD1200 wrote:
Did you turn on the breaker in the panel?
Yeah, that gave me power to the “Line” wires. They have power all the way to the disconnect box, but the “Load” wires running to the mini split don’t have any power. It seems likely it’s something in that disconnect box.
SEEMEFIRST
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SEEMEFIRST 2/12/2022 1:24pm
2/12/2022 1:24pm
Does the part that says "on-off" pull out?
If so, that is the fuse able link, I think.
If it comes out, check it across the blades for continuity.
It also may be directional. So it only works one way.
SEE ARE125 2/12/2022 1:27pm
2/12/2022 1:27pm
SEEMEFIRST wrote:
Does the part that says "on-off" pull out? If so, that is the fuse able link, I think. If it comes out, check it across the...
Does the part that says "on-off" pull out?
If so, that is the fuse able link, I think.
If it comes out, check it across the blades for continuity.
It also may be directional. So it only works one way.
Yeah that comes out. The way it’s in currently is ON but you can take it out, flip it over and reinstall it for OFF. That’s really the only two ways it can go. You’re saying there should be a fuse in that part somewhere?
SEEMEFIRST
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SEEMEFIRST 2/12/2022 1:39pm
2/12/2022 1:39pm
SEEMEFIRST wrote:
Does the part that says "on-off" pull out? If so, that is the fuse able link, I think. If it comes out, check it across the...
Does the part that says "on-off" pull out?
If so, that is the fuse able link, I think.
If it comes out, check it across the blades for continuity.
It also may be directional. So it only works one way.
SEE ARE125 wrote:
Yeah that comes out. The way it’s in currently is ON but you can take it out, flip it over and reinstall it for OFF. That’s...
Yeah that comes out. The way it’s in currently is ON but you can take it out, flip it over and reinstall it for OFF. That’s really the only two ways it can go. You’re saying there should be a fuse in that part somewhere?
That whole thing is a fuse.
When you pull it, you should see 2 blades on each side.
Those make the circuit. You should have continuity between the two.
Not from each side, but individually.
It makes contact from black to black, and the red to white.
That make any sense?
SEEMEFIRST
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SEEMEFIRST 2/12/2022 1:45pm
2/12/2022 1:45pm
Here's mine.


SEEMEFIRST
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SEEMEFIRST 2/12/2022 1:49pm
2/12/2022 1:49pm
Your disconnect could have bad connections where those blades go in if the fuses are both good.
With the fuse pulled, you should have power where the blades plug in.
If not, something is wrong with the disconnect.
SEEMEFIRST
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SEEMEFIRST 2/12/2022 1:50pm
2/12/2022 1:50pm
Your disconnect could have bad connections where those blades go in if the fuses are both good.
With the fuse pulled, you should have power where the blades plug in.
If not, something is wrong with the disconnect.
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SEE ARE125 2/12/2022 2:00pm
2/12/2022 2:00pm Edited Date/Time 2/12/2022 2:03pm
SEEMEFIRST wrote:
Does the part that says "on-off" pull out? If so, that is the fuse able link, I think. If it comes out, check it across the...
Does the part that says "on-off" pull out?
If so, that is the fuse able link, I think.
If it comes out, check it across the blades for continuity.
It also may be directional. So it only works one way.
SEE ARE125 wrote:
Yeah that comes out. The way it’s in currently is ON but you can take it out, flip it over and reinstall it for OFF. That’s...
Yeah that comes out. The way it’s in currently is ON but you can take it out, flip it over and reinstall it for OFF. That’s really the only two ways it can go. You’re saying there should be a fuse in that part somewhere?
SEEMEFIRST wrote:
That whole thing is a fuse. When you pull it, you should see 2 blades on each side. Those make the circuit. You should have continuity...
That whole thing is a fuse.
When you pull it, you should see 2 blades on each side.
Those make the circuit. You should have continuity between the two.
Not from each side, but individually.
It makes contact from black to black, and the red to white.
That make any sense?
Gotcha, I was thinking a more traditional fuse like would be in a car or something, but larger. Any chance I blew a fuse when I flipped the main breaker back on? Here’s what I got:


The prongs are offset from each other for some reason.
SEEMEFIRST
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SEEMEFIRST 2/12/2022 2:11pm
2/12/2022 2:11pm
Check for continuity between the two straddling your thumb, and the other side too like I'm doing in the top pic.
Also leave the fuse out, and check for power where the fuse plugs in.
SEE ARE125 2/12/2022 2:17pm
2/12/2022 2:17pm Edited Date/Time 2/12/2022 2:21pm
I may have figured it out. From Home Depot’s website on the disconnect box:


So I guess I need to get some fuses, apparently they aren’t included. Any suggestion in which type? Says H, K1, K5, K9, etc.
SEEMEFIRST
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SEEMEFIRST 2/12/2022 2:21pm
2/12/2022 2:21pm
That would explain the weird prong set up.
I think you found the problem.

Good luck!
SEEMEFIRST
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SEEMEFIRST 2/12/2022 2:22pm
2/12/2022 2:22pm
If there's no continuity between the prongs, that's it for sure.
SEE ARE125 2/12/2022 2:23pm
2/12/2022 2:23pm
Thanks for all the help! Any idea which fuse class to get?

Pit Row

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SEEMEFIRST
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SEEMEFIRST 2/12/2022 4:08pm
2/12/2022 4:08pm
I start running out of talent when talking fuse class.

You might consult the A/C manufacturer.

I would guess a fast acting one, that would provide the most protection.
SEE ARE125 2/12/2022 4:15pm
2/12/2022 4:15pm
Thanks, the guy at Home Depot started laughing when I told him I looked it all over multiple times trying to figure it out. He showed me which fuses I needed and it’s working great now. Just in time to watch some SX in comfort. lol Thanks again for all the help, I sort of feel like a dumbass. haha
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SEEMEFIRST
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SEEMEFIRST 2/12/2022 5:32pm
2/12/2022 5:32pm
Glad she's running.
sumdood
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sumdood 2/12/2022 10:53pm
2/12/2022 10:53pm
SEE ARE125 wrote:
Thanks, the guy at Home Depot started laughing when I told him I looked it all over multiple times trying to figure it out. He showed...
Thanks, the guy at Home Depot started laughing when I told him I looked it all over multiple times trying to figure it out. He showed me which fuses I needed and it’s working great now. Just in time to watch some SX in comfort. lol Thanks again for all the help, I sort of feel like a dumbass. haha
Hahaha ......stupid instructions who reads those Laughing Good news is it works and you're an expert on it now, win win.

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