water tank heating 12v or 110 from inverter?

[FWGolden]

Looking to use a small 10 gal. hot water tank in an RV application. Question is, what would be a better option, staying with the 110v element or converting to a 12v element. Thank you in advance.

Frank

 

[Cdkipp]

I am interested in the answers. One thing that occurs to me is that you need to think about more than just the element. Going to 12 volt from 120 volt would increase the amps used by 10x and thus require larger diameter wire.

 

[efficientPV]

Stay with 120V as it gives you more options like site power. It takes 1.5KWH to heat that much water. Installing more than a 300W heater at 12V is impractical and that would take 5 hours. You likely have a 1.5 or 2KW heater. Something like a 1KW heater would be more practical for your inverter. If it would fit a 3500-4500W 240 element would be that, 1/4 power.

 

[OffGridInTheCity]

In our camper, we have a Bosch 120v 5gal hot water heater on a switch that we turn on when we want it but leave it off most of the time.
For ongoing hot water we use an InSinkErator (https://www.build.com/product/summary/1128354) at the sink. This maxes out at 700w and is well insulated and provides sink hot water (as apposed to showering hot water) for minimum overall power.

It's so hot you can poor it into the single-cup K-Cup and it's 99% heated already, reducing the power the K-Cup pulls. You can dribble it into a pan and mix with cold water for 'hot water' etc.....