Two window AC' s on one circ ok?

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ritelec

ritelec

Senior Member
Location
Jersey
Hello all
I brought several AC circs out a throughout a home.
I was originally going to run twenty amps per.
The windows are small and the current ACs are small
120v 4.8 amps each. So I ran fifteen amp circs instead. Home runs to the panel.
To save on AFCI breakers any issues with running two
On one circ ? Does 125% plus 100% apply here?
4.8x1.25 = 6 plus 4.8 = 10.8.
Or is there some article that says it has to be rated 350%
And if in jersey 695% ???

Thank you.
 
G

Gregg Harris

Senior Member
Location
Virginia
Occupation
Electrical,HVAC, Technical Trainer
ritelec said:
Hello all
I brought several AC circs out a throughout a home.
I was originally going to run twenty amps per.
The windows are small and the current ACs are small
120v 4.8 amps each. So I ran fifteen amp circs instead. Home runs to the panel.
To save on AFCI breakers any issues with running two
On one circ ? Does 125% plus 100% apply here?
4.8x1.25 = 6 plus 4.8 = 10.8.
Or is there some article that says it has to be rated 350%
And if in jersey 695% ???

Thank you.
Click to expand...

440.62 Branch-Circuit Requirements. (A) Room Air Conditioner as a Single Motor Unit. A room air conditioner shall be considered as a single motor unit in determining its branch-circuit requirements where all the following conditions are met:

(1)
spacer.gif
It is cord-and-attachment-plug-connected.

(2)
spacer.gif
Its rating is not more than 40 amperes and 250 volts, single phase.

(3)
spacer.gif
Total rated-load current is shown on the room air-conditioner nameplate rather than individual motor currents.

(4)
spacer.gif
The rating of the branch-circuit short-circuit and ground-fault protective device does not exceed the ampacity of the branch-circuit conductors or the rating of the receptacle, whichever is less.

(B) Where No Other Loads Are Supplied. The total marked rating of a cord-and-attachment-plug-connected room air conditioner shall not exceed 80 percent of the rating of a branch circuit where no other loads are supplied.

(C) Where Lighting Units or Other Appliances Are Also Supplied. The total marked rating of a cord-and-attachment-plug-connected room air conditioner shall not exceed 50 percent of the rating of a branch circuit where lighting outlets, other appliances, or general-use receptacles are also supplied. Where the circuitry is interlocked to prevent simultaneous operation of the room air conditioner and energization of other outlets on the same branch circuit, a cord-and-attachment-plug-connected room air conditioner shall not exceed 80 percent of the branch-circuit rating.
 
ritelec

ritelec

Senior Member
Location
Jersey
Dennis Alwon said:
You are fine with 2 units on one 15 amp cir. IMO
Click to expand...

I agree

electricmanscott said:
Electrically probably fine but I'll bet the say "use on individual branch circuit" or something like that.
Click to expand...

If that was a "I'll bet they say"... there is no they.

Gregg Harris said:
440.62 Branch-Circuit Requirements. (A) Room Air Conditioner as a Single Motor Unit. A room air conditioner shall be considered as a single motor unit in determining its branch-circuit requirements where all the following conditions are met:

(1)
spacer.gif
It is cord-and-attachment-plug-connected.

(2)
spacer.gif
Its rating is not more than 40 amperes and 250 volts, single phase.

(3)
spacer.gif
Total rated-load current is shown on the room air-conditioner nameplate rather than individual motor currents.

(4)
spacer.gif
The rating of the branch-circuit short-circuit and ground-fault protective device does not exceed the ampacity of the branch-circuit conductors or the rating of the receptacle, whichever is less.

(B) Where No Other Loads Are Supplied. The total marked rating of a cord-and-attachment-plug-connected room air conditioner shall not exceed 80 percent of the rating of a branch circuit where no other loads are supplied.

(C) Where Lighting Units or Other Appliances Are Also Supplied. The total marked rating of a cord-and-attachment-plug-connected room air conditioner shall not exceed 50 percent of the rating of a branch circuit where lighting outlets, other appliances, or general-use receptacles are also supplied. Where the circuitry is interlocked to prevent simultaneous operation of the room air conditioner and energization of other outlets on the same branch circuit, a cord-and-attachment-plug-connected room air conditioner shall not exceed 80 percent of the branch-circuit rating.
Click to expand...

Thank you Gregg ...............Two going on one circuit.


Thanks guys.
 
Last edited:
electricmanscott

electricmanscott

Senior Member
Location
Boston, MA
ritelec said:
I agree



If that was a "I'll bet they say"... there is no they.



Thank you Gregg ...............Two going on one circuit.


Thanks guys.
Click to expand...

It was a they. Two air conditioners would be a "they" to me. They, as in the two air conditioners usually say, not out loud of course, to use an individual branch circuit.
 
ritelec

ritelec

Senior Member
Location
Jersey
electricmanscott said:
It was a they. Two air conditioners would be a "they" to me. They, as in the two air conditioners usually say, not out loud of course, to use an individual branch circuit.
Click to expand...

Yes........
but in this install there's nothing wrong with it...right.........?

two loads.......together under 12 amps on a 15 amp circuit...............
 
iwire

iwire

Moderator
Staff member
Location
Massachusetts
ritelec said:
Yes........
but in this install there's nothing wrong with it...right.........?

two loads.......together under 12 amps on a 15 amp circuit...............
Click to expand...

It's fine as long as the listing and labeling does not require individual circuits.

There is a strong chance the listing and labeling of each unit requires seperate circuits.
 
K8MHZ

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
iwire said:
It's fine as long as the listing and labeling does not require individual circuits.

There is a strong chance the listing and labeling of each unit requires seperate circuits.
Click to expand...

Yep.

The sticker on mine says, in bold print, "Use on single outlet circuit only".

It's rated for 8.6 amps.

The single outlet requirement may be part of the UL listing for window air conditioners.
 
ritelec

ritelec

Senior Member
Location
Jersey
I'll check to see if they're labeled that way..........
I'm "assuming" it's a small AC and there meant to plug into any convenience outlet..........but, the listing may be on it to cover their ars........

Thanks guys.
 
ritelec

ritelec

Senior Member
Location
Jersey
Just a heads up....
No sticker saying use on single outlet circuit.

Only mentions use time delay or circuit breaker 15 amp.

Thanks again gents.
 
G

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
ritelec said:
Just a heads up....
No sticker saying use on single outlet circuit.

Only mentions use time delay or circuit breaker 15 amp.

Thanks again gents.
Click to expand...
You are welcome. Current majority interpretation is that it does not have to be on a sticker. Just within the instruction/installation manual for the unit is enough.
 
ritelec

ritelec

Senior Member
Location
Jersey
GoldDigger said:
You are welcome. Current majority interpretation is that it does not have to be on a sticker. Just within the instruction/installation manual for the unit is enough.
Click to expand...

You know.........I'm going to go on a limb here........ But it's not on the unit and may or may not be in the manual...

I'm thinking at 4.8 amps...their selling these units with maybe the intent of not needing and electrician or separate circuit.

Shoot, it's less than a hair dryer or these heaters they sell....
 
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