Heating water in silence (via inverter)

[MikeTC]

After my 620ah agm bank is full (typically around mid day) I frequently use my 2000w cont inverter to heat shower water heater with 1200w element. Can't do this in NZ winter with 800w solar.

[yachtgemini]

a 12-volt hot water heater is s l o w and in a marina it will rely on the battery charger. It really is a good option if you spend a lot of time on the hook with surplus wind and solar... this is all about compromise.

However, there is also another option depending on where you cruise which is to use a hydronic (water heating) diesel heater from Espar etal and have a separate coil in the water tank. This is a great option if you are cruising higher latitudes and doing a major system upgrade.

Personally I would avoid loading up the inverter and batteries with a big resistive load like a water heater. Sure the inverter will do it and you may get lucky but it is increasing your risk of failure.

Depending on the age of your hotwater tank you may also want to consider getting a tank with fittings for 2 immersion heaters and swap one out for a 12 volt unit.

You could end up spending a lot of money in pursuit of that shower while 50 cent ear plugs may solve your noise problem.