Perhaps its the specific flowswitch that is used on the El Diablos. (I used a propane burner for years from Duuuane that was a completely different flowswitch which didn't have that much of an issue)
I usually pull out the inside of the switch with the spring and just clean it up sometime polish it a bit and put it back and its good as new. But like I said its never a problem with regular water or acid rinse but with powder emulsifiers.
Two specific emulsifiers that presented the stuck switch problem. Rage and Kleenline (Shawn F). I can't comment on other powders because I never use them.
I use regular fresh water not soft water.
The termostate I set at 230-240.
When the switch is stuck the flame is on and I have watched my pressure build up over 2000psi inside the unit just from the heating up. I do think that it is rather dangerous for the system and or the person nearest to the heater.
I think the temp sensor is too far from the actual heater on the Diablo and even if you had it set at 150, the heater may explode before the steam from the out of control heater reaches the temp sensor.
I suggested to Masterblend a couple years ago, that the temp sensor should be a lot closer, if not inside, the diesel burner for safety. That way it would shut down the flame even if the flow switch is stuck on the on position.
)
