Hvac vavs

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hhsting

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So I have 7 vavs fed from on branch circuit #1.

Vav-1: MCA: 0.28A, MOCP: 15A
Vav-2: MCA: 0.28A, MOCP: 15A
Vav-3: MCA: 0.28A, MOCP: 15A
Vav-4: MCA: 0.28A, MOCP: 15A
Vav-5: MCA: 0.28A, MOCP: 15A
Vav-6: MCA: 0.28A, MOCP: 15A
Vav-7: MCA: 0.28A, MOCP: 15A

My #1 branch circuit breaker size provided is 20A that feeds all 7 vavs above. Cable size provided is #14 awg.

Would the branch circuit #1 breaker size be 15A or 20A?
 
hhsting said:
So I have 7 vavs fed from on branch circuit #1.

Vav-1: MCA: 0.28A, MOCP: 15A
Vav-2: MCA: 0.28A, MOCP: 15A
Vav-3: MCA: 0.28A, MOCP: 15A
Vav-4: MCA: 0.28A, MOCP: 15A
Vav-5: MCA: 0.28A, MOCP: 15A
Vav-6: MCA: 0.28A, MOCP: 15A
Vav-7: MCA: 0.28A, MOCP: 15A

My #1 branch circuit breaker size provided is 20A that feeds all 7 vavs above. Cable size provided is #14 awg.

Would the branch circuit #1 breaker size be 15A or 20A?
Click to expand...
15A
 
hhsting said:
So I have 7 vavs fed from on branch circuit #1.

Vav-1: MCA: 0.28A, MOCP: 15A
Vav-2: MCA: 0.28A, MOCP: 15A
Vav-3: MCA: 0.28A, MOCP: 15A
Vav-4: MCA: 0.28A, MOCP: 15A
Vav-5: MCA: 0.28A, MOCP: 15A
Vav-6: MCA: 0.28A, MOCP: 15A
Vav-7: MCA: 0.28A, MOCP: 15A

My #1 branch circuit breaker size provided is 20A that feeds all 7 vavs above. Cable size provided is #14 awg.

Would the branch circuit #1 breaker size be 15A or 20A?
Click to expand...
Are you familiar with the term MAXIMUM overcurrent protective device?
 
hhsting said:
My #1 branch circuit breaker size provided is 20A that feeds all 7 vavs above. Cable size provided is #14 awg.

Would the branch circuit #1 breaker size be 15A or 20A?
Click to expand...
There are two issues here, one the #14 conductors on a 20 amp OCPD and two the use of a 20 amp OCPD when the maximum permitted OCPD for any of the VAV's is 15 amps.
 
infinity said:
There are two issues here, one the #14 conductors on a 20 amp OCPD and two the use of a 20 amp OCPD when the maximum permitted OCPD for any of the VAV's is 15 amps.
Click to expand...

This is hvac VAV. Cable size would depend on MCA correct? So #14 awg is good for 15A and total MCA is less than 15A all 7 no?
 
hhsting said:
This is hvac VAV. Cable size would depend on MCA correct? So #14 awg is good for 15A and total MCA is less than 15A all 7 no?
Click to expand...
Yes, I think that you've got it. It needs to be on a 15 amp circuit with a conductor sized for a minimum of 15 amps.
 
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