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100 amp panel #41288 08/24/04 03:14 PM
Joined: May 2004
Posts: 49
jayson Offline OP
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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Re: 100 amp panel #41289 08/24/04 03:23 PM
Joined: Jan 2004
Posts: 66
cpalm1 Offline
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

Re: 100 amp panel #41290 08/24/04 07:18 PM
Joined: May 2003
Posts: 2,876
e57 Offline
60A tops if the thing (AC) is a real beast, sounds sketchy?

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"Well - I oughta....." -Jackie Gleason
Re: 100 amp panel #41291 08/24/04 07:36 PM
Joined: May 2004
Posts: 697
Dave55 Offline
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?


Re: 100 amp panel #41292 08/24/04 08:47 PM
Joined: Apr 2002
Posts: 914
Electric Eagle Offline
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.

Re: 100 amp panel #41293 08/24/04 09:16 PM
Joined: May 2004
Posts: 49
jayson Offline OP
the 100 amp breaker is feeding a diconnnect with a 60 amp breaker.

Re: 100 amp panel #41294 08/25/04 08:36 AM
Joined: Aug 2001
Posts: 16
Geno Offline
What size is the wire?

Re: 100 amp panel #41295 09/03/04 01:53 PM
Joined: Jul 2002
Posts: 241
SJT Offline
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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