Why not install 400amp service instead of 200 when upgrading?

[wwhitney]

I would consider an electric dryer as a continuous load

A continuous load is defined by the NEC as: "A load where the maximum current is expected to continue for 3 hours or more." So unless your dryer has a cycle that last 3 hours, and it runs its heater and motor and any other loads at full tilt for the full 3 hours, it's not a continuous load.

Cheers, Wayne

 

[STS-134]

Dryers are not continuous loads, so there would be nothing wrong with 7.2 kW (30A) dryer, but I don't know that any such electric dryers exist.

Cheers, Wayne

Good point. But I've never seen a 30A dryer either.

I would consider an electric dryer as a continuous load- the heating element is on for the duration of the drying cycle. When my dryer turns on you see a large spike in usage that lasts roughly an hour.

It's actually not. The dryer, whether electric or gas, cycles the heating element/burner on and off to maintain a certain temperature. It doesn't run it continuously. If you start an electric dryer and go outside to your electric meter you'll be able to see the heating element cycling. If it's a gas dryer, you should be able to hear the burner cycling by listening to your gas meter.

 

[ucmndd]

23 amps is a healthy amount of usage. It's more than my 3 or 4 ton AC's use combined.

That seems unlikely, unless you have incredibly efficient / new AC units. A dryer pulling 23 amps is drawing about 5.5kw. A good rule of thumb for AC units is 1kw per ton when running, so ~7kw for 7 tons.

That assumes continuous draw of course, which isn't the case for either the dryer or the AC units as they cycle the heating element / compressor, but I'd bet a nickel that running 7 tons of AC for an hour (in any reasonably warm weather) is going to draw more power than a clothes dryer running for an hour.

 

[Laketime]

That seems unlikely, unless you have incredibly efficient / new AC units. A dryer pulling 23 amps is drawing about 5.5kw. A good rule of thumb for AC units is 1kw per ton when running, so ~7kw for 7 tons.

That assumes continuous draw of course, which isn't the case for either the dryer or the AC units as they cycle the heating element / compressor, but I'd bet a nickel that running 7 tons of AC for an hour (in any reasonably warm weather) is going to draw more power than a clothes dryer running for an hour.

I am only going off of my Tesla app, not actual draws. The first pic is from last summer when the temps were over 90 and our AC was cranking. (We have 8 tons total but the last ton is an inverter mini split that uses very little power).

This pic is from last week. Those 2 spikes are from when the dryer was turned on.