Hi, I am installing wiring for a new central air condenser that is being installed next week, and I wanted to make sure I was not missing anything. The HVAC installer told me that I needed #8 and 40 amps. I have a flexible whip to go from the disconnect to the condenser and have run (2) #8 wires plus a ground across my basement to the breaker box. I bought a 60 A disconnect box (is this the proper size? Only size Lowe's had) and it has an on/off switch rather than a pull out or a fuse style. Does the type matter? Inside this box I assume I hook up the wires from the circuit breaker to the line terminals and the wires from the condenser to the load terminals, is this correct? Finally I wasn’t quite sure which circuit breaker to buy, I know 40 amps and I’m pretty sure it’s a 2 pole, and hacr but other than that is there anything to the circuit breaker selection? Anything else I might need to know to keep this wiring job up to code would be helpful. Thank you.

Sounds like you are on top of it. You must have a disconnect near the unit. I don't think it needs to be to be fused. Fuses add extra protection and are easier to change if the load requirements change. They are also one more thing to check when there is a problem. ''Where did I put the spares?'' Mine are stapled to the wall by the breaker box. No problem using a 60 amp disconnect on a 40 amp circuit. A little oversize never hurts. Chances are, the installer will point out any mistakes.

The unit should be prewired, only needing the 2 power feed wires, ground, and coil wires connected.

I replaced the plastic flex my installer furnished with rigid conduit after the dog chewed a hole in it. I also replaced the plastic disconnect with a metal one. I have a great neighbor. I went next door and said ''Dan, I want to borrow a hickey.''. He gave a quizzical look, and then said ''Do you want 1/2'' or 3/4''?''. Hickey is a common term for a conduit bender. She also chewed up the control wires and insulation on the vapor tube.

The dog survived, and is now working as a dog guide. The ones I have now are decent types that wouldn't do that.

img src="http://www.photolocker.net/images/Labman/KatetheAC.jpg"

Thanks labman - I do have a very "chewy" lab so I am worried about the insulation and wires. I thought the wires going to the unit had to be flexible though? Any idea on the type of circuit breaker?

Frankly I don't know if flex is required. I do know it is easier and works fine in normal cases. I felt a little extra work was worth it to protect a highly valuable dog. You can buy a nice car for what a trained service dog costs. We sometimes have an assortment of working dogs, puppies, breeding stock, plus dogs with only emotional value out in our yard.

As for the circuit breaker, any double pole 40 amp that fits your box should work. Most boxes list the types of breaker that will fit.

Thinking some more about the fuses. Check the name plate rating on your condenser. It may draw less than the 40 amps. I have a 30 amp breaker, but 25 amp fuses. The 40 amp breaker will protect the wires, but not the unit if it draws less power. If you decide you need fuses, and Lowe's doesn't have what you need, try a True Value or Ace Hardware or an electrical supply house.

Photolocker offers 4 different formats for each picture. I think I have the right one for a picture of Kate between the armored A/C and the copper pipe extending outside the fence to protect the garden hose to open. I put a stove pipe over the tubing and control wires.

http://www.photolocker.net/images/Labman/KatetheAC.jpg

OK thank you - the stove pipe might be a good idea for me too. That insulation is going to be pretty tempting

Old fan has 3 wires. New fan has 4. do I tape up one of the brown wires?