[C320-list] Basic hot water heater and charging question

[Greg Flanagan]

Gene,

I doubt your hot water tank is getting power from any of those sources. The draw would be tremendous. Your hot water tank is likely getting heated by your fresh cooling water circulation from your engine when it is running. You probably have a switch somewhere that opens a gate to let your your engine cooling water circulate and exchange heat with your HW tank. 

My HW tank can be heated 3 ways: shore power with a breaker on my AC panel; by running my hydronic furnace (this is Canada); or by opening the gate with a solenoid switch to circulate the engine cooling water. The latter method really drops the engine temp which is great if your engine is getting a little warm on a hot summer day. My HW tank never uses DC house power. 

Cheers,

Greg 
Sidney, BC 
Hoop Dancer #1076

> On Sep 15, 2018, at 4:52 PM, Gene Helfman <genehelfman at gmail.com> wrote:
> 
> Very basic: from where does the hot water heater draw electricity?  Is it
> off the battery bank?  The alternator? The battery when the alternator
> isn't charging?
> 
> I ask because we are having alternator problems when motoring.  Or maybe
> voltage regulator problems.  We get full charging for 30-35 minutes
> regardless of battery state, then it shuts off, meaning we are then drawing
> from the house 4Ds. When we shut the engine off (an hour or more later), we
> have lots of hot water. We're concerned that once the alternator shuts off,
> the water heater is still drawing power until the WH thermostat shuts it
> down.
> 
> If so, is there an easy way to turn the hot water heater off.  It isn't an
> obvious toggle on the instrument panel.
> 
> thanks,
> gene
> Satori, #398, 1997
> -- 
> Gene Helfman, Professor Emeritus
> Odum School of Ecology, University of Georgia
> PERMANENT address:
>    498 Shoreland Dr., Lopez Is., WA 98261
>    (360) 468-2136
>    genehelfman at gmail.com
> 
> *Zero tolerance is great for building airplanes but not for running
> countries.*