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#41288 - 08/24/04 01:14 PM 100 amp panel
jayson Offline

Registered: 05/12/04
Posts: 49
Loc: russellspringsky
in a house panel with a 100 amp main can u put a 100 amp breaker on the bus . like if in the panel i have 2 20 amp lighting circuit breakers and 30 amp and 50 amp range and a 100 amp below that feeding central air unit.any help would be aprecicated thanks

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#41289 - 08/24/04 01:23 PM Re: 100 amp panel
cpalm1 Offline

Registered: 01/06/04
Posts: 62
you should not have a 100 amp breaker on the A/C it should be 20, 30, or 40 amps depending on the A/C units rating

#41290 - 08/24/04 05:18 PM Re: 100 amp panel
e57 Offline

Registered: 05/27/03
Posts: 2837
Loc: S.F.,CA USA
60A tops if the thing (AC) is a real beast, sounds sketchy?
Mark Heller
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#41291 - 08/24/04 05:36 PM Re: 100 amp panel
Dave55 Offline

Registered: 05/08/04
Posts: 666
Loc: Crystal Lake, Illinois, USA
Typically, the wire is sized to the load, and the breaker matches the wire size. There are other circumstances, of course. What is the air conditioning load, and the wire gauge?


#41292 - 08/24/04 06:47 PM Re: 100 amp panel
Electric Eagle Offline

Registered: 04/20/02
Posts: 928
Loc: Alpharetta, GA
It is posible to have a 100 breaker for A/C, it's very common around here to have a 100 amp breaker serving a disconnect for 3 or 4 A/C units rather than having 3 or 4 diferent home runs for each unit.

To answer the guy's original question, yes it is posible, but if the A/C's draws a combined load anywhere near that 100 amps, it's too much for the panel with all the olther stuff.

#41293 - 08/24/04 07:16 PM Re: 100 amp panel
jayson Offline

Registered: 05/12/04
Posts: 49
Loc: russellspringsky
the 100 amp breaker is feeding a diconnnect with a 60 amp breaker.

#41294 - 08/25/04 06:36 AM Re: 100 amp panel
Geno Offline

Registered: 08/27/01
Posts: 16
Loc: Syracuse, NY USA
What size is the wire?

#41295 - 09/03/04 11:53 AM Re: 100 amp panel
SJT Offline

Registered: 07/24/02
Posts: 242
Do you have a range and a dryer on this panel also? It sounds like you need to upgrade to a 200 amp service. Things would be OK, but then the 60 amp load of the AC arrives on the scene.
Very possible the main could trip. Is it worth living with that chance?


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