Hot water isolation valves

[S/V AMITY]

   Have a Westerbeke W44B tied with the domestic H/W tank.  Does anyone see a problem with installing valves to isolate the feed & return engine coolant lines to the H/W tank?  Reason for doing so would be to loop-out the tank in case the tank develops a leak where the coolant leaks into the fresh water side of the tank or vice versa.

[S/V Deo Volente]

I built a manifold with valves to isolate the water heater, and the "bus" heater, as well as a valve to shut off the bypass. This way I can heat the water faster by shutting the bypass. On long runs under power I shut off the water heater to keep it from boiling over. 

[S/V AMITY]

OK, thanks!

[S/V AMITY]

  Has anyone here worked out a thermostatic control somewhere in the HW system to control the temp? 160 deg. right from the HW tank coming out of a tap or shower is not good.  I know there are thermostatic shower control valves for house use (required by code)... might one of those be adaptable for our systems?

[S/V AMITY]

  Found this:  https://www.amazon.com/Atmama-Thermostatic-Mixing-Connections-Temperature/dp/B08781SRCW/ref=sr_1_25?dchild=1&keywords=water+temp+mixing+valve&qid=1606935268&sr=8-25

Should solve the problem.