Originally Posted by rlevesque
Thanks for your input.
The faucets of both showers are closed so this is not the cause. The problem occurs with all hot taps.
There is a little bit of water leaking at valve#1 (cold inlet). From comments seen here I think it is 99% sure the valve is broken, in other words when I turn the handle nothing happens inside and the valve remains closed.
I will make a post once the problem is solved.
My best regards,
Ray, if you want to verify this before going to all the trouble of removing/replacing the cold water inlet valve...here is how I might do it.
Close the crossover valve, so no cold water can backfeed the tank. You can close the top hot water outlet valve too, but it's not totally necessary for our test purposes.
If you are currently plugged into a form of 120 volt shore power, Make sure your electric heating element switch (if equipped) on the face of the water heater is off. it's explained here in case you aren't familiar with it.
Suburban's electric switch and much more
Now remove your anode rod to drain the tank. Leave the anode rod out. Once drained (and with the anode rod still removed), then either connect to city water or your fresh water tank via your pump and see if water starts shooting out the anode rod hole.
If not, change the position of the cold water inlet handle and see if there is a change, and water starts coming out the anode rod hole. If no again, then you know that water is not coming into the tank, and that cold water inlet valve is most likely bad.
EDIT: it looks like we were both typing and posting at the same time. Your post above this confirms the same as mine would. You might can change the cold water inlet valve position both ways and test...just to be sure.