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0 pointsmasklinn6mo ago0 comments

> share one 20A residential circuit

15, dishwasher manufacturers can't assume the dishwasher is on a 20.

0 comments

This plus the comment about sharing a circuit with an oven. If the oven is electric, even in the US it is 220v. If it is gas only, then it could be 120v as it only needs to run the igniter and other circuitry without running any heating elements.

bcoates6mo ago

I think he said sharing a circuit with a fridge, which are generally 110 in the US -- i think this is how my apartment is wired (2-phase 30A to oven dedicated, one 20A for the whole rest of kitchen)

Trying to run a resistive heater on the same circuit as a fridge compressor without tripping leans towards very conservative wattage

Scoundreller6mo ago

That's funny. Code in Ontario Canada is that the fridge needs to be on its own circuit. It's funny because we have an extra-big-ass inverter drive fridge that never draws more than an amp or two, even at startup because it's inherently soft-start.

Just a waste of copper and a beaker really.

Johnny5556mo ago

>Just a waste of copper and a beaker really.

But also helps avoid the case where your coffee maker trips the breaker shared with your refrigerator and you don't notice until the food in the refrigerator is warm. (which was a risk in my previous apartment - the counter circuits were shared with the refrigerator). I think it makes sense to have it as a separate circuit.

3 more replies

matt-attack6mo ago

Refrigerators have become incredibly efficient in the last 40 years. I mean incredibly.

It sounds like this law is outdated.

inferiorhuman6mo ago

Electric ovens in the US have required dedicated 40 or 50 amp circuits for decades per the NEC. Dishwashers, as well, have required dedicated circuits for a while but the 20 amp requirement is a more recent development (although it's probably been at least a couple decades).

Kitchens in general have required 20 amp general purpose circuits since at least the early 80s. However the NEC (but not the Canadian equivalent) allows for 15 amp duplex receptacles on 20 amp circuits so home builders looking to save a few pennies often use those. Besides, there are few if any, residential appliances out there that have NEMA 5-20 plugs. Then again hardwiring dishwashers was pretty common up until recently.

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