Heat pump wiring question


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Old 06-27-15, 08:25 AM
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Heat pump wiring question

Quick code question. I'm doing the wiring myself for two separate ductless heat pump units (2 outdoor units each with one indoor head). Both draw 6.5 amps at 220 and it calls for 14 awg wire and 15 amp breaker. Is is legit to run a 12 awg 20 amp to a single disconnect and split from there to the two units or do they have to have their own dedicated circuits? The outdoor units would be right beside each other and the disconnect right there.

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Old 06-27-15, 08:32 AM
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Look at the nameplate of the units. It will list the maximum overcurrent protection allowed which I would suspect will be 15 amps. Make sure you are looking at the right amp draw because 6.5 amps sounds fairly light to me.

I would suggest running a single feeder (20A) to two fused outdoor disconnects. Outdoor A/C disconnects are only about $10 for fused ones. Then install the proper sized fuses for each heat pump.
 
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Old 06-27-15, 08:43 AM
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Yes the 6.5 amp draw is correct. They are both 1.5 ton units. It does not ask for a fused disconnect. Does using 2 fused disconnects allow for the single run back to the breaker box to be code compliant? The run is not very long and two 15 amp breakers versus a 20 is not a ton of money either but it would save space in my panel to use a single 20.

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Old 06-27-15, 09:43 AM
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Does using 2 fused disconnects allow for the single run back to the breaker box to be code compliant?
No. It makes the connection to the heat pumps code compliant. Code requires you follow manufacturers instructions. The manufacturer requires 15 amp protection. A fuse disconnect with 15 amp fuses provides that.
 
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Old 06-27-15, 12:19 PM
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Again, look at the nameplate of the units. It will say max fuse, circuit breaker, overcurrent device, or MOPD. This is what you will need to protect the unit with.
 
 

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