Adding Electric Element to Espar Hydronic D5

Hi Everyone,

Yet another Espar related question! We'd like to add an electric element to our set up so that we can use that rather than diesel in the rare instances where we have access to shore power. We purchased this block heater but it's not working with our system, I don't think it has enough power.

Has anyone done this and if so, what electric element did you use?

Appreciate any help or advice!
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If I remember Highschool, 1kWh equals around 3400btu/h. Dunno offhand what the btu/h that Espar is supposed to turn out, but I think its about 10k.
Thats likely right, your electric1kW element is too small.

If you just want camper heat on admittedly rare occasion plugged into mainspower. A small space heater is far less expense and hassle. Of course thats simple lowtech therefore unworthy of legitimate ’ExPo Guys.
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I would suggest having a small (2 gal) aluminum tank made. Add a threaded bung for a standard home water heater element. I would suggest 2kw. Then add 2 barb fittings for the hydronic hoses. A thermostat would be needed, so either one linked to the existing control scheme, or one attach to the tank.

The D5 is 5kw.
Years ago we got a "Comfort Hot" from I think Rixens (though they seem to have evolved since then) to add to our Hurricane Hydronic furnace for our sailboat. The comfort hot is pretty simple, it is a rectangular aluminum tank with 2 1500 watt water heater elements in it (much like luthj is suggesting). It also acts as the expansion/fill and has a radiator cap on it. It needs to be the highest component in the heating system. We have a dedicated 30 amp shore power outlet for it. On the Comfort Hot I placed an aquastat, this controlled the furnace if the Comfort Hot could not keep up with demand. It worked well on a 40' sailboat in Boston to about 20 degrees F. Then the diesel furnace would occasionally kick in to compensate. I am considering building something similar for our RV build.