This is; how to replace a broken or melted disconnect, for an air conditioning unit.

First thing is go turn off the power at the main electrical panel. Turn off the breaker usually labeled AC and goes to the condenser.

After you think the power is off, grab your volt meter and be sure there’s no power.

Now that you’re safe and power is off, use a common screwdriver to loosen all the wires.

Undo all the small wire nuts holding together the thermostat wire. Break apart all the thermostat connections but remember how they go together.

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Now use a thick common screwdriver and a hammer on the locknut holding the electrical, liquid tight whip onto disconnect. Loosen the locknut by spinning it counter clockwise.

Now remove the electrical connection from disconnect all together.

Unscrew disconnect from the wall.

If, disconnect is glued to the wall. Use a razor knife or screwdriver to carefully break the seal.

Remove disconnect from wall.

Now Take your new disconnect, set it on the ground and with a small tipped screw driver and a pair of crimpers. Break out the 2 knockouts to match the old disconnects holes.

(Note: To remove the knockouts perfectly can take some practice. Here’s how I do it. I pound down on the second thickest ring until both its sides are close to each other. I then squeeze them together with a pair of linesman and work them both back and forth until it breaks off. I then use a pair of crimpers to cut off any remaining pieces invading me 3/4” hole.)

Now screw disconnect to the same spot the old one was mounted and reconnect the electrical whips exactly as before. Don’t forget to put your locknuts back on the whips.

Now put the 2 ground wires, 1 from each whip into the ground nut and tighten them down.

Push the ground wires back and out of the way.

Put both the wires from the home to the line side of disconnect. L1 and L2

Put the 2 thicker wires from the air conditioning system itself to the load side of disconnect T1 and T2

Push all the connections you just made in and out of you way so you’ll be able to close the cover later.

Put together all the thermostat connections as you found them but cleaner.

Now use a common screwdriver to double check that all the connections are tight.

Put the cover back over the wires, and go turn on the AC breaker at the electrical panel.

Now put an amp probe on the AC unit when you start it. You need to be thinking about why that disconnect burned.

A disconnect can burn from either loose connections or too much power through a wire that’s too thin to handle it.

When you start the unit and watch for high starting or running amps.

(Note: If you see starting amps above 40 even for 1/10th of a second then you need to install a hard start kit to prevent premature compressor failure from high heat on the windings at every start a compressor that pulls high amps on start is not using that power so it becomes heat.)

If it pulls higher than 40 amps on start you’re going to need a kick start kit so move to step 16 now.

If the Compressor starts up fine and never pulls over 40 amps then you could be done, but move to the end test page to be sure.

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