Load calculations and grounding

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New User
Lima ohio
Retired handyman
How do I calculate loads to determine what size of my main breaker should be.
I have 55Amp furnace with a second 30amp breaker
30 amp water heater
50amp range
30amp a/c
2 20amp window a/c s
30amp dryer
20amp washer
20 amp outside receptacle
2 15amp bathrooms
20 amp refrigerator
2 15amp dining room
2 20 amp bedrooms

20 amp living room
What size main should I have

as I have a 100 amp panel with a 50amp mobile home power supply cord that went bad burned and corroded under the home connecting to a 4 wire female receptacle.
the feeders are 6/2 4/1 no ground the home is not grounded to the service disconnect also 100 amp or any ground rods as I can tell.
grounds and neutrals are bonded in the service panel but not to the chassis or water pipes or conduit
The only ground wire is in the 50 amp cord witch goes to nothing it's not connected in the box as the are only 3 feeders are my feeder wires big enough as the run 30 under ground


Chief Moderator
Staff member
Durango, CO, 10 h 20 min without traffic from wing
Licensed Electrician
I am closing this thread in accordance with the Forum rules.
This Forum is for professional electricians, inspectors, engineers, and other members of the electrical industry. We are not permitted to provide “how-to” assistance to a person who is not employed in this industry.
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