I know my son turns the heater on an hour or two before using. The timer for the unit is 20 mins. rinse with water immediately afterward the cleaner is caustic. I will find out from him excactly where he gets the cleaner. I asked him one day about adding cleaner and I remember him saying its a special Super Clean cleaner. It is in a 5 gal white plastic container that he uses.
here are my heads before and the after the cleaner
And yes those are all the same parts including the valves