Suburban Hot Water Heater Issue.

I still go with a spider web. You need to pull the tube off so you can find the orifice. Do not poke anything through the hole in the orifice, but do firmly wipe it off with something. Then clean off everything downstream of the orifice. Find a way to push and pull a rag through all the chambers for the flame. After that put it back together and I'll bet it fires.

I've also read on here about some kind of oil that can pool in propane lines and cause problems. If cleaning doesn't help I would probably turn off the propane bottles and disconnect the propane line. Then open a bottle slowly to see if you have good gas flow.