Water heaters are treated separately. Branch circuits must be 125% of the
nameplate rating. Nec 422.13


"Doug Miller" wrote in message
et...
In article , "RBM" rbm2(remove
wrote:
Your water heater wiring, while incorrect, has nothing to do with the main
disconnect problem. You are correct that a 4500 watt heater requires a 30
amp circuit and #10 wiring and that a 3500 watt unit would work fine with
the existing wiring and breaker

4500W / 240V = 18.75A

Should be OK on a 20A circuit, no? The 80% rule applies only to continuous
loads, defined as "maximum current expected to continue for three hours or
more." Shouldn't an electric water heater be able to reach temp in much
less
than three hours?

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.