I am concerned by the size-selection' s installation of an "80A Service-Disconnect" on a 200A uni-pak, to feed the nearly 2,200 square feet modern house with a 5 Tons HVAC central system. Very modern and over-sized appliances including Sub-Zero like refrigerator as well as numerous recessed lights.
The residential work, Southern California, is recently completed by an electric contractor?
The property has a gas-fired tankless water heater, gas stove-Oven appliance.
Does current load calculation for capacity design assumes meeting 70%-80% of the current need, therefore leaving 30%-20% for potential future need, i.e, expansion or load changes need?
Is the 80A size sufficient? it does not look like there is room for expansion, if any is desired in the future.
Best Answer
The minimum service size in the NEC current code is 100a (Ca. may have an exception) the wire to the service can be derated 83%. I don’t know how they got away with a smaller service but all gas appliances 60amp would probably be fine, even A 48” sub zero doesn’t draw that much power especially if full I love mine. And the 5 ton ac is probably the largest load on the system at about 30 amps , the total lighting and receptacle load would be 28 amps if everything was maxed out so you still have room for garbage disposal trash compactor etc. the dryer may be electric and if everything and I mean everything is on at the same time it probably would be ok because of load diversity load calculations are covered in article 220 of the NEC if you want to look them up.