clyst
Well-Known Member
Hi Guys ...... in theory is it possible to connect ,as an example , a 2000w inverter to a 1500w calorifier without burning everything out ?
Inverter to heat water via calorifier .
- Thread starter clyst
- Start date
vas
Well-Known Member
yep, as long as your inverter is well wired and the batteries can provide the necessary 160+A @12V or 80A@24V you should be fine.
just do the calcs how long the batteries will last doing so
just do the calcs how long the batteries will last doing so
clyst
Well-Known Member
Thanks for your prompt reply Vas.... althought i have a bank of trojan batteries i expected to run engine for all or part of the water heating . ( engine heating also contrabuting to heating water )
rogerthebodger
Well-Known Member
We find heating water with engine heating is more then adequate and olly heat with mains when in dock
pvb
Well-Known Member
Of course you can use your inverter as well as the engine to heat your water more quickly. I imagine you have some sort of sensible battery monitor; use that to make sure that your batteries end up near to full charge.
vas
Well-Known Member
how many trojans, how big, what V?
I have 4X6V T105RE for 24V and regularly run my watermaker (circa 1800W) at anchor. Usually lunchtime with the batteries full from the 600W solar. Still using a victron Multiplus 3000VA inverter, batteries drop quickly to 22V when you're pulling 80+A@24V. Granted running the engine at say 1000rpm and pumping 30A does help a lot (especially if solar is also adding in the equation.
I have 4X6V T105RE for 24V and regularly run my watermaker (circa 1800W) at anchor. Usually lunchtime with the batteries full from the 600W solar. Still using a victron Multiplus 3000VA inverter, batteries drop quickly to 22V when you're pulling 80+A@24V. Granted running the engine at say 1000rpm and pumping 30A does help a lot (especially if solar is also adding in the equation.
clyst
Well-Known Member
Iv 4 x 6v 145s giving 2 banks of 12v . 3oow solar with vitron regulator
RupertW
Well-Known Member
Running your engine to heat via its calorifier is a far more efficient way to heat water than running the engine to use the alternator via invertor to heat.
But if you have solar and your batteries get to float well before dusk then you can use the excess to heat water. I have relays which keep dumping spare solar into the hot water coil ,adding in a builder’s portable 240-110v to step the 1500w to 375w to closer match solar input.
But if you have solar and your batteries get to float well before dusk then you can use the excess to heat water. I have relays which keep dumping spare solar into the hot water coil ,adding in a builder’s portable 240-110v to step the 1500w to 375w to closer match solar input.
vas
Well-Known Member
I think you've mentioned this before and I got confused, can you please elaborate? how the 1500W goes down to 375?
I bought a seaward 20gal water heater (still in the garage!) and its I think 1850W, wouldn't mind dumping excess solar to it. Having said that we've used the boat now for 4 seasons without hot water and none complained
V.
ip485
Well-Known Member
Yes you can, but consider a Hydronic heater if you want to do it "properly". It is a better option for hot water always on demand, where ever you are, and without resort to any power.
greeny
Well-Known Member
Sounds interesting. Hot water with no power. How do we do this? Hang a bag in the sun, or is it some form of water heating solar panel?
Hoolie
Well-Known Member
Half the voltage means half the current through the heating element; so Power = Volts x Amps is down to 25%.
RupertW
Well-Known Member
I bang on about it at any opportunity as it’s my favourite YAPP of the year - even though all it solves is running the engine for 20 minutes once a day.I think you've mentioned this before and I got confused, can you please elaborate? how the 1500W goes down to 375?
I bought a seaward 20gal water heater (still in the garage!) and its I think 1850W, wouldn't mind dumping excess solar to it. Having said that we've used the boat now for 4 seasons without hot water and none complained
V.
The way the coil goes down to 1/4 of the power is that I use a 220v-110v transformer - a little portable one used commonly by builders.. I could probably have got one cheaper but this was easy to buy and very robust.
(The theory that tells you this is Ohms Law (V=IR) and P=VI plus a little bit of algebra tells you that for a fixed resistance (the immersion coil) the power goes up or down by the square of the voltage change - so 1/2 volts gives 1/4 power, and 1/20 volts (for example if you used 12v on a 240v coil) gives just 1/400th of the power).
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vas
Well-Known Member
as it happens, I do have an old 220-120 transformer, so will try it next summer, I hope it's man enough for the 1500W of the heater resistor!
alas the main issue is finding it in the garage...
alas the main issue is finding it in the garage...
RupertW
Well-Known Member
As long as it’s rated above 375w (or 3.5 amps at 110v) then it’s powerful enough
vas
Well-Known Member
should be it's approx 150mm cube (not in a box) and bloody heavy! that of course if I manage to find it!
ip485
Well-Known Member
Well maybe not absolutely no power!
A hydronic heater is a very small heater than runs on diesel (the same as an Ebber air) and heats the water to the calorifier.
I am incredibly pleased with this setup. Sips diesel and enables you to have hot water on demand with a tiny current draw purely for the pump so you are independent of the mains, the need to run the Genset or blitz the batteries.
There is really nothing not to like, if you spend time on the hook or away from shore power.
RupertW
Well-Known Member
That makes sense but there is something very satisfying about spending a week at anchor using no diesel or petrol at all.
rogerthebodger
Well-Known Member
Black plastic pipes laid around you deck and pumping the resulting hot water through your calorifier.
Dogone
Well-Known Member
I do this on my boat. Works fine.