I have a Roberts Gordon 80k BTU heater in my garage that has just recently started to backfire. When it is trying to ignite, it makes two loud bangs back to back and then stops trying to ignite until the next cycle.
Anyone ever had a problem like this? It was recently converted over to natural gas using the kit from the manufacturer. I'm wondering if its a gas inlet setting that is off, or if there is a leak in the pressure valve.
**Edit** This usually happens when it is very cold 10 deg Fahrenheit or below.