Calculation on breaker

floatr

Member
Location
tn
I'm upgrading my outside 100 amp panel to the new heat pump an wanted to calculate if I will need a 60 or 50 amp double breaker on the 9.5 kw heat kit.
I have #6 wire .The information on unit/kit says
mca is 49 ,mop is 50 .
.I saw in another post someone spoke on the math % calculation an it looks like I'd need 55 or 60 if 125% applies ---?

I saw this ~
10,000 watts divided by 240 is 41.6 amps. This is a "continuous load" so the wires must have an ampacity of 125% of 41.6 amps, which is 52 amps.Apr 30, 2008
 

curt swartz

Electrical Contractor - San Jose, CA
Location
San Jose, CA
Occupation
Electrical Contractor
The manufacture has already done the math. 49 amp minimum circuit size and 50 amp maximum overcurrent protection. 50 is your only option.
 

SSDriver

Member
Location
California
Yep, if they list MCA and MOP the only thing you have to look up is conductor ampacity rating to meet MCA, no math(well besides ampacity corrections depending on bundling and temperature, etc).
 

floatr

Member
Location
tn
Hmmm I pulled up the same model# of my kit for sale online - hkp 10c online for sale an its requiring 60..--

.copied
Specs page--- Kilowatt9.5 Amperage Requirement (Circuit 1 / Circuit 2)60 / 0 amps Voltage208 - 240 Volts Voltage Phase1 ACCESSORIES
 

floatr

Member
Location
tn
It's really odd with another site an all the same specs same Part -saying 50 amp


..Kilowatt(kW):9.5Voltage:208-230VCircuit Breaker Size (Amps):50 Why Buy From Us? RELATED PRODUCTS
 

Jraef

Moderator
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
MOP is 50A at 208V, 60A at 240V.

If that confuses you, at 208V the heater elements use less power because of the lower voltage but the same resistance in the element.
 

floatr

Member
Location
tn
Thanks yes ,so going by my actual sticker an kit info mine would use the 60 amp breaker ? ..9.5@240 volts like the 1st link had. An is sold with it ?

I guess I'll run#6 @60amp breakers to it.
 
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