Primus questions

[jdaniel]

The Primus baseboard heaters have always worked well in my 1991 (coach 279) until now. It doesnt get too cold here in Alabama so it doesnt come up very often. The electric heat is always enough. Last year I had all the hoses in the engine compartment replaced including the ones going to the Primus. Recently I turned it on and it would not work. On my front control, the light will come on briefly and then go out for several minutes. I checked the breakers and fuses and they are fine. Nothing tries to heat.
How do I make sure water is even in the Primus?? Where do I go from here? The manual says the flush the system every two years but doesnt mention how??
Ideas?

Thanks,
Jimmy