Williams heater

Does anybody know anything of about these heaters. I’ve never seen one. I’m reading the manual but was curious if anybody knew more info. The unit appears to meet clearance but the single wall vent pipe doesn’t. The flame was very orange in my opinion.

You have the manual. If something does not match what the manual says, write it up and recommend a cleaning and service at the same time. (That will take car of the flame.)