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Single family home load calculation for panel size.

Cyelectric

Member
Location
47711
Occupation
Apprentice
Home has turned into a nightmare with constant change orders. Looking for help figuring out service size. Wire size. Currently roughed a 400 amp service.

5000sq ft home
3- a/c units 30 amps at 240v per
3- high efficiency furnaces at 8 amps 120v per
1- 1 hp ejector pit
1- 1 hp sump pump
1- microwave 15 amps/1800 watt
1- garbage disposal 1 hp
1-dishwasher 12 amp
1- fridge 18 amp
1- washer/dryer 20 amps
4- towel warmers 2.2 amps per
3- steam dehumidifiers 16 amp per
1- tile heater 14 amps
10- small appliance counter top circuits
2 - gas garage heaters 10 amps per
Now has added
Swimming pool sub panel 100amps
5- Tesla charges 50 amp at 240 v per
6- electric heaters at 240v 20 amps per
 

charlie b

Moderator
Staff member
Location
Lockport, IL
Occupation
Semi-Retired Electrical Engineer
We can help. But we prefer that members first show us how they have approached the problem. Have you started a calc? How did you come up with 400 amps for the service rough-in?
 

Cyelectric

Member
Location
47711
Occupation
Apprentice
We can help. But we prefer that members first show us how they have approached the problem. Have you started a calc? How did you come up with 400 amps for the service rough-in?
sq ft 5000x3va 15000 va
counter top circuits 10x 1500 15000
bath 6 at 1500 9000
water heater high efficency 2 1920
sump 1 746
ejector 1 746
tile heater 1 1680
microwave1 1800
hood 1 500
garbage disposal 1 1250
dishwasher 1 1440
fridge 1 960
washer dryer 1 2400
towel warmers 4 at 2.2a 120v 1056
steam dehumidifier x 3 5760
total 55898
-10000 at 100%
45898 X .40= 18359.2

total 28359.2 / 240 = 118.2a

garage heater 20 amp 120v x 2 2400
furnace high efficency 3 x 8 amps 120v 2880
electric heaters 6 at 240 v 20 amp 28800
total 34080 / 240 = 142a

a/c unit 3 240v 30 amp 21600



electric vehicle charger 240v 50 a x 5
pool sub panel 100a
 
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