I'm installing a 17,500 btu A/C window unit. Its 220 volts, It says it requires a 15 amp breaker. I think all i'll need is 14/2 wire for 15 amps but im thinking of going with 12/2 just for the added saftey and protection. Should I also go with a 20 amp breaker with the 12/2, Or should i use a 15 amp and 12/2 Or should i just use the 14/2?
electrical advice needed
- Thread starter -Clayton-
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cant go wrong going over spec on a circuit. Who knows what the future will bring.
If it were mine I would go for the 12 ga. The lower voltage drop is easier on the AC, although you might not ever notice the difference. It also gives you the option of adding a bigger unit later if you decide to.
A 15 Amp breaker would offer more protection for the AC motor if it doesn't have adequate internal protection. In the real world, it prolly doesn't matter.
If I'm going to the effort of running a new circuit, I would never dink around with 14 gauge wire. The small extra cost for 12 gauge and the small amount of extra work dealing with the heavier wire is insignificant unless you are building a housing tract.
There are situations where you might want a smaller circuit breaker to protect a single load, but don't waste your time running 14 gauge.
A 15 Amp breaker would offer more protection for the AC motor if it doesn't have adequate internal protection. In the real world, it prolly doesn't matter.
If I'm going to the effort of running a new circuit, I would never dink around with 14 gauge wire. The small extra cost for 12 gauge and the small amount of extra work dealing with the heavier wire is insignificant unless you are building a housing tract.
There are situations where you might want a smaller circuit breaker to protect a single load, but don't waste your time running 14 gauge.
I don't suppose it needs an N, so you could run two wire with an ground, but is it even legal in your area to use 14/2 for such a circuit? 12/2 is the minimum.
The device requires a 15 amp breaker on a 15 amp circuit? Or are they saying 15 amp minimum? I would use a 20+ amp circuit and have a local 15 amp breaker - IF that's what they are asking for.
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Its 220 volts, It says it requires a 15 amp breaker.
The more I think about this, they must mean near or at the device.
The device requires a 15 amp breaker on a 15 amp circuit? Or are they saying 15 amp minimum? I would use a 20+ amp circuit and have a local 15 amp breaker - IF that's what they are asking for.
Quote:
Its 220 volts, It says it requires a 15 amp breaker.
The more I think about this, they must mean near or at the device.
Kestas
Staff member
I may be wrong, but aren't most homes wired with 14 ga. as standard throughout the house, with 12 ga. for the kitchen and other high-draw places, and 12 or 10 ga. for 220v applications?
I went through this when I was wiring the house for my 220v compressor. The book said 14 ga would work, but somewhere I got the hint that 12 or 10 ga is more appropriate.
I went through this when I was wiring the house for my 220v compressor. The book said 14 ga would work, but somewhere I got the hint that 12 or 10 ga is more appropriate.
Originally Posted By: Kestas
I may be wrong, but aren't most homes wired with 14 ga. as standard throughout the house, with 12 ga. for the kitchen and other high-draw places, and 12 or 10 ga. for 220v applications?
Spec houses thrown together by cheap developers looking to save every cent are often 14 ga.
I may be wrong, but aren't most homes wired with 14 ga. as standard throughout the house, with 12 ga. for the kitchen and other high-draw places, and 12 or 10 ga. for 220v applications?
Spec houses thrown together by cheap developers looking to save every cent are often 14 ga.
Originally Posted By: -Clayton-
Pablo, It says 15 amp time delay circuit breaker or fuse. So I guess that means at the box?
No. Absolutely to me this means locally. It's the right way to do a 240v device anyway. Costs a bit more, but is best for safety, maintenance, legality, etc
Pablo, It says 15 amp time delay circuit breaker or fuse. So I guess that means at the box?
No. Absolutely to me this means locally. It's the right way to do a 240v device anyway. Costs a bit more, but is best for safety, maintenance, legality, etc
I think they mean at the box but I don't see why a you couldn't go to a 20 AMP circuit. This will give you some wiggle room for start up and the 15 AMP is probably a min. spec.
I always use 12 ga wiring for 20 Amp or lower.
I always use 12 ga wiring for 20 Amp or lower.
Use a 15 amp breaker like it specifies. Per electrical code, you are to follow the instructions that come with the appliance and if it specifies a 15 amp breaker..guess what..you should use one.
It doesn't need to be local, it can be in the load center. In fact, I'm not even sure how you'd properly install a local circuit breaker without using a small breaker box and then guess what, it's considered a sub-panel so now you need 4 wires to it (hot,hot,ground,neutral).
You can use 12AWG wire if you like, but 14AWG wire is acceptable given the 15 amp circuit breaker requirement.
It doesn't need to be local, it can be in the load center. In fact, I'm not even sure how you'd properly install a local circuit breaker without using a small breaker box and then guess what, it's considered a sub-panel so now you need 4 wires to it (hot,hot,ground,neutral).
You can use 12AWG wire if you like, but 14AWG wire is acceptable given the 15 amp circuit breaker requirement.
I can almost guarantee you that you are putting twice the amount of A/C in that window that you need. You are waaaaaayyy better off using a smaller unit and running it more. It dehumidifies much better.
I have a 6800BTU unit in my addition window. It cools an 18 x 20room with a cathedral ceiling and an adjacent kitchen/dining area. It runs 100% of the time and does a great job. Most people over air-condition.
I have a 6800BTU unit in my addition window. It cools an 18 x 20room with a cathedral ceiling and an adjacent kitchen/dining area. It runs 100% of the time and does a great job. Most people over air-condition.
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I'd agree in terms of central air, Al. Most opt for the V8 sized unit when they should be running a 4 banger for best performance. I never explored load:size factoring, but something like a 75% duty cycle during the peak demand was considered sensible. For most that means a 25k btu unit or smaller (depending on the size of the house). Most get into "bigger is better"
Window units may cool a much larger area than the room that they're placed in. It would be hard to match the COLD localized temps of a room unit with central air ..let alone the push of a window unit with central ventilation. The trade off is typically the noise factor. Naturally, temp isn't even throughout the cooled area.
Go big with the wiring man! You never know when you need to run a welder or lathe in your dining room. During a remodel I actually drug in my tig welder once to fuse some stainless brackets together in my kitchen (THIS WAS DEFINITELY "WHITE TRASH BEAUTIFUL" AND NOT ENDORSED AS SOP)!! Obviously I wasn't married at the time, and my neighbors loved the pretty blue lights that emanated from my windows at night. :no-no:
Originally Posted By: brianl703
Use a 15 amp breaker like it specifies. Per electrical code, you are to follow the instructions that come with the appliance and if it specifies a 15 amp breaker..guess what..you should use one.
It doesn't need to be local, it can be in the load center. In fact, I'm not even sure how you'd properly install a local circuit breaker without using a small breaker box and then guess what, it's considered a sub-panel so now you need 4 wires to it (hot,hot,ground,neutral).
You can use 12AWG wire if you like, but 14AWG wire is acceptable given the 15 amp circuit breaker requirement.
I don't think a singular use local box is considered a load center, and can be 120V, one leg.
Use a 15 amp breaker like it specifies. Per electrical code, you are to follow the instructions that come with the appliance and if it specifies a 15 amp breaker..guess what..you should use one.
It doesn't need to be local, it can be in the load center. In fact, I'm not even sure how you'd properly install a local circuit breaker without using a small breaker box and then guess what, it's considered a sub-panel so now you need 4 wires to it (hot,hot,ground,neutral).
You can use 12AWG wire if you like, but 14AWG wire is acceptable given the 15 amp circuit breaker requirement.
I don't think a singular use local box is considered a load center, and can be 120V, one leg.
I will be cooling approx 500 sq ft with it so it should be about right. I have a smaller unit for the rest and the nightime. I've decided to go with 12ga wire and the reccomended 15 amp breaker. I know the workers at lowes would not have been so helpfull.
Installing a 220 volt receptacle How-To.
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Originally Posted By: -Clayton-
I will be cooling approx 500 sq ft with it
Ah. You like frigid air! Me too. Heck with that comfortable stuff. Give me relief.
I bet you can get the room down below 60F.
I will be cooling approx 500 sq ft with it
Ah. You like frigid air! Me too. Heck with that comfortable stuff. Give me relief.
I bet you can get the room down below 60F.
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I don't think a singular use local box is considered a load center, and can be 120V, one leg.
You're required to have overcurrent protection in both legs.
I suppose one could use a fused air conditioner disconnect. I have never seen one of those used for a window unit. They're big and really wouldn't look all that great hanging on an interior wall. I don't know why one would bother with that given that it's not necessary.
I don't think a singular use local box is considered a load center, and can be 120V, one leg.
You're required to have overcurrent protection in both legs.
I suppose one could use a fused air conditioner disconnect. I have never seen one of those used for a window unit. They're big and really wouldn't look all that great hanging on an interior wall. I don't know why one would bother with that given that it's not necessary.
Of course on both legs for a 240V circuit....I was just saying that you could even have a local breaker for single leg for a 120V device...
But I agree about the looks.
But I agree about the looks.
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