Different amp breakers

[john2016]

If I have an existing 3P90A breaker in a panelboard located in the electrical room and need to change out the existing breaker in the mechanical room to a 3P60A enclosed breaker on the other end feeding an air handler that is being replaced in the mechanical room located across the building is this allowable per code? The wire size from the 3P90A breaker is 3#2, 1 #10GRD going to the 3P60A enclosed breaker. From the 3P60A enclosed breaker to the AHU the wire size is 3#6, 1 #10GRD. Thanks.

 

[Dennis Alwon]

You don't need to change the breaker at the source as long as the correct overcurrent protective device is used at the units disconnect.

 

[john2016]

Thank you Dennis. For reason I was thinking the breaker sizes had to match so I thought since there is a 3P90A in the existing panel it would need to be changed to a 3P60A breaker so the breaker sizes would match on both ends. Thanks for the clarification. I still have a lot to learn...