Originally Posted by HowieE
With a friend. While you are outside with the refigerator access door open, the burner view port open, and preferably in darker light have someone go inside the trailer. While you are looking in the view port have them turn the refigerator on in gas mode. You shold see or hear the igniter attempt to light the burner, a very small spark.
Does the popping occur when the flame ignites and then goes out? It will help if you can see the flame, eg. your helper and you may have to do this at night if it is difficult to see the flame. It will be small and steady should be blue. The thermocouple should be positioned to be heated by the flame. As already mentioned, a good cleaning is the 1st place to start. Sometimes compressed air is enough, sometimes an old toothbrush will be helpful to clean the burner slots. It is tempting to stick a wire into the office but that is not a good idea. Solvent and compressed air is the better way. If those steps fail and your gas supply is adequate, then the pressure regulator could be the culprit or possibly the electronics board. Inspect and reseat any push on electrical connections and inspect and tighten any screw down connections. The pressure is measured with a manometer and it may be a good idea to seek professional assistance.
If you find the little white cotton balls in or around the burner, they are the webs from the previously mentioned spiders. They also can cause trouble at the water heater, furnace and sometimes the pressure regulator. If you prefer not to use mothballs, I've had excellent results using dog flea collars. I wrap one around the gas line at each location so that it stays out of the way, maybe about 4-6 inches from the burner. I replace them every year or two and haven't had any more spiders in over 20 years.