I have an EXCELLO model PA 100 propane heater in my garage. The heater kicks on, furnace lights (bottom of heater gets warm) but then shuts down. I have not been able to find anything on this brand name. I've found Reznor and Modine that looks like it but no type of x reference between Excello and them. Was Excello bought out? I need a wiring diagram and start sequence to see what the problem is. Any advice is appreciated.