12v hot water heater?

[Momac]

Refit time! And I'm looking for a small and efficient 12v instant hot water maker, for basin washing only, not to power a shower.
Are there any new-ish devices which will do this, without being attached to a generator? This only has to heat perhaps 2l at a go and run straight off a 125Ah battery, so charging requirements aside.
Size and cost are the most important considerations.
TIA

Will you not have gas hob on your boat? If so you already have a means of heating water so there you have the solution at no cost and no extra space required.
Diesel fuelled water heating is possible but not cheap.
http://www.webasto.com/gb/markets-products/marine/heating-solutions/water-heaters/water-heaters/
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[Seagreen]

Oh now that's a usable idea. Something like a Calorimiter, but in a heads locker, not by the engine.

 

[prv]

Oh now that's a usable idea. Something like a Calorimiter, but in a heads locker, not by the engine.

If you don't mind the price and can find the space, I reckon a diesel water heater (Mikuni, Kabola, etc) is the ideal. It's basically a seagoing version of a domestic oil-fired central heating boiler, giving you unlimited cabin heating and hot water independent of the engine.

Pete

 

[Seagreen]

Just expanding on the concept idea a little, I'd not like to wrestle a kettle of water along the passageway into the cramped head, so the 'kettle' idea would have to plug in locally. This leaves calorifiers, and the provision of lagged pipe runs, I presume. This is awkward but not impossible. I've never really used a calorifier in anger.
Would it be more efficient to have a calorifier running off the engine heat exchanger (given that the engine will get a fair amount of daily use) and therefor located in the engine space, or would it be better to have a smaller calorifier located in the heads to provide direct short pipe runs, but running off alternator charging?

 

[Seagreen]

It would have to replace a wheezy Taylors 068 cabin heater, but its do-able in principle.

 

[lw395]

Just looked on ebay, you can buy 'kettle' type elements of 500w 230V etc quite cheaply.
Which means a cheap inverter and realistic size wiring is a possibility.
If you only boil the water you actually need it seems reasonable.

If your tank water is OK, no reason not to make tea from the calorifier water, so should be able to boil that from 70degC reasonably quickly.

The other 12V water heating I'm aware of is some Ford Mondeo diesels have heater elements in the heater hoses for demisting, I think these are pretty watty!

Would not be without a calorifier, I think it is the first step towards a boat being civilised?

 

[Seagreen]

Of course, now I'm on the whole water heater/cabin heater combi merrygoround. Water heater, and pumped warm cabin air. The cabin size is about the internal size of a sadler 26, if that gives you any ideas.

 

[prv]

Would it be more efficient to have a calorifier running off the engine heat exchanger (given that the engine will get a fair amount of daily use) and therefor located in the engine space, or would it be better to have a smaller calorifier located in the heads to provide direct short pipe runs, but running off alternator charging?

Vastly, vastly more efficient to have one running on the waste engine heat, not electricity.

It doesn't even need to be in the engine space if that's a problem for some reason.

Pete

 

[Momac]

My boat has a calorifier as do a lot of motorboats, which takes heat from the engine. The tank is lagged but not the pipework.
It has an immersion heater for use when connected to shore power .

 

[prv]

My boat has a calorifier as do a lot of motorboats, which takes heat from the engine. The tank is lagged but not the pipework.
It has an immersion heater for use when connected to shore power .

Exactly the same arrangement on most yachts. It's a no brainer if you have an inboard engine and want hot water.

Pete

 

[pikeyrm]

http://www.whalepumps.com/Marine/pr...px?Category_ID=10054&FriendlyID=Water-Heaters

I have been looking at these in the past and decided against it due to the power required.