Frymaster Dean 2424G Deep Fryer "natrually" Questions

we have a dean deep fryer model SR42GNS on start it makes a big boom and a large blue flame comes out of stack on top? is the fryer propane or natrual gas?It sounds like the orfices,burners or baffles

frymaster blowing back fire hi first let me ask you to locate amanual for sg14d1-s.Now my next problem is just before ignition i am getting a big boof just before full ignition.I have a beautifull ...