Burner resonance? my propane furnace sounds like a spray plane when the burners are...
my propane furnace sounds like a spray plane when the burners are lit why
Answers: It is pretty normal for propane.
Propane boils at -38 degree F. Although it is bought and sold as a liquid, it comes into you burner as a gas, near quite a bit of pressure. As the cistern gets lower, so will the pressure. You should hear the commotion diminishing then.
The just real concern beside propane should be if you smell the "rotten egg" smell. You usually smell it when you first turn on your stove, but if it is present any other time, you may have a dribble and that needs to be fixed.
Most newer gas furnaces use what is call in shot burners. They enjoy advantages but they tend to be a little more ear-splitting than the old ribbon style burners. For more info, check out the furnace page at my source.