Problem with diesel heater on our Diablo it will not turn on all the time. When we run the water directly from the machine out of the pressure release we are good however when we run the wand the heater doesn't fire any ideas?
Like Gerson said or flow switch may need a good cleaning. Check inline filter on wand. Does the jets on the wand have little screens? All these things can slow flow down causing the heater to not fire. Also check quick connects. Sometimes they get crap stuck on them or worn and don't connect as well when newer.
Yep, sounds like a flow problem alright. The El Diablo has a safety system that will not allow the heater to fire up if there is insufficient water flow. If cleaning the flow switch (sometimes it needs to be replaced BTW) and/or the filter on your wand doesn't solve the problem, call Master Blend and talk to their service department. The guys there are great and will walk you through the steps you need to take to fix the problem.
Def the flow switch under the heater. Pull switch. Open it up and pull the spring out. Cut the spring so it barely comes out of the top when it's in the switch. It will allow the heater to come on with lower pressures. Some guys just take the spring out completely. But your switch must be vertical if your going to do that.