Cooling the ESC


I think using the forward motion of the foil to ram water through the tube is attractive for it’s simplicity but I worry about debris clogging the tube causing the ESC to be damaged from overheating. Having the waste water vent out in a highly visible location is a great common sense sanity check that cooling water is flowing as expected.

Another approach might be a closed loop cooling system using the hollow metal foil mast as both a heat sink and coolant reservoir of clean water. Might help keep the wires cooler too.


Which pumps are people using for water cooling the ESC?


Dumb questions:

  1. why don’t you put the ESC inside of the mast or propulsion casing so that it can dump heat into the water via the conductivity of the surrounding aluminum?
  2. Does the battery unit itself need active cooling? (On ebikes they are often air cooled)


There isn’t a lot of room inside the mast for the esc. Not sure about the batteries, it probably depends on which batteries you have.


What do you all think of these aluminum enclosures? I think they will do better with the heat than the poly carbonate boxes. IP67 waterproof, is that enough?


We are using our jet nozzle as the has incredibly high flow, and runs more water as you use more mower self regulating cooling demand. A 90 brass elbow Tapped into nozzle and waterline up the inside of mast. We did this with our ducted propeller setup last fall as well and it also worked well.

Can you recommend an ESC?

Is closed cooling esc system smart? It would remove need of washing the tube after each use (salt, dirt, seaweed). Could aluminum mast be a good heatsink? Silicon tubes would go from esc through the whole mast and back, with some anticorossive coolant or whatever?


I use a closed system. A plexitank 900ml heats up from 20 to 45 C in a session semms to work fine.


Is it so difficult to dissipate the heat? The ESC is used underwater, we should use water to dissipate it, I’m considering to add 2 pipes in the ESC heat sinks , the pipes will be full with water. I’m going to share you my pictures after I finished it.


Other than aditional weight, i see no drawbacks. U use pure water or some other liquid? I am guessing only Hiorth brotherz need some antifriz. :wink: Hope your knee getting well!


Just water and I suppose I can go down on the water volume too.