sizing motor circuit protect: heat pump/supplemental electric heat & blower package
I need help sizing motor circuit protect: heat pump/supplemental electric heat & blower package
I have a new fan in the attic that draws about 2A 230v.
I just found out that there is a supplemental electric heater [KFCEH0401N03] that draws 12a at 240v.
There is a new package unit outside with compressor/fan that draws 16.1 FLA at 240v. It's a real 240v from a delta supply.
My original idea was to use the old AC feed with existing 30a cb and put a
GE manual motor starter
with the
16a heater in it
as a local disconnect and wire the whole thing in #10. I was going to use another manual starter at the blower with a two amp heater in it, also wire it in #10.
The CBs protecting the whole thing are very old too I must say.
First, I don't know if that idea would've been ok because I can't continue because the supplement heat is now to be provided for.
Anyway, now I have to run another circuit back to the old main and get a blower/heater 2p ct.
Is my original idea ok for the package unit, that is to have it under the 30a 2p, run it using the old #10's and then disconnect the unit with a local [toggle] manual motor starter that has a 16a heater strip for protection?
Can I downgrade my blower disconnect to simply a two pole 20a toggle on my new 20a 2p circuit for the blower and sup heat? Downgrade, that is, because of no fuse.
Usually these things have fused disconnects next to them, but when I sized the needs, this seemed adequate. Am I missing something because the original breakers are not HVAC rated? Or because the breakers are sized for the wire but I have to interrupt the load from the disconnect with breakers sized at 125% to allow for inrush or locked rotor?
At the blower/heater, since it is just a squirrel cage, there doesn't seem too much chance of it locking up. It seems not much different from the blower on a FAU that is just protected by a summer switch.
Thanks Guys!
I need help sizing motor circuit protect: heat pump/supplemental electric heat & blower package
I have a new fan in the attic that draws about 2A 230v.
I just found out that there is a supplemental electric heater [KFCEH0401N03] that draws 12a at 240v.
There is a new package unit outside with compressor/fan that draws 16.1 FLA at 240v. It's a real 240v from a delta supply.
My original idea was to use the old AC feed with existing 30a cb and put a
GE manual motor starter
with the
16a heater in it
as a local disconnect and wire the whole thing in #10. I was going to use another manual starter at the blower with a two amp heater in it, also wire it in #10.
The CBs protecting the whole thing are very old too I must say.
First, I don't know if that idea would've been ok because I can't continue because the supplement heat is now to be provided for.
Anyway, now I have to run another circuit back to the old main and get a blower/heater 2p ct.
Is my original idea ok for the package unit, that is to have it under the 30a 2p, run it using the old #10's and then disconnect the unit with a local [toggle] manual motor starter that has a 16a heater strip for protection?
Can I downgrade my blower disconnect to simply a two pole 20a toggle on my new 20a 2p circuit for the blower and sup heat? Downgrade, that is, because of no fuse.
Usually these things have fused disconnects next to them, but when I sized the needs, this seemed adequate. Am I missing something because the original breakers are not HVAC rated? Or because the breakers are sized for the wire but I have to interrupt the load from the disconnect with breakers sized at 125% to allow for inrush or locked rotor?
At the blower/heater, since it is just a squirrel cage, there doesn't seem too much chance of it locking up. It seems not much different from the blower on a FAU that is just protected by a summer switch.
Thanks Guys!
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