suburban nt30sp furnace problem?

[lazer man]

Hello my name is lance im new here! Thanks for letting me join. i have a c oachmen catalina with furnace trouble ugh! I got the camper a few years back and enjoyed camping in indiana.all the systems seemed to work ok ac,lights,monitor etc.winter came and i had it stationary at my maintenance shop which was a distance from home.i stayed there occasionally and a bitter cold spell came.the furnace was working what seemed ok.im going to simplify as im going by memory from then and doing research now! The furnace would,thermostat set,clicking,delay,fan,ignite,heat cycle etc. Then one nite i woke freezing fan running no idea how long cold air. Checked tanks,ok reset thermostat goes thru motions again seems ok camper up to heat.go to sleep does it again next morning i fill tanks my brother worked for tom raper/best buy rv and suggests new hoses/regulator so i replace at tanks.it kinda warms up thru the day and seems to work ok.that nite same thing.i get online for trouble shoot and somewhere see a 5/16 gap for igniter now i know incorrect.anyway playing with gap would intermittent help.(im mechanically/electrically inclined)not familiar with propane furnaces.i thought tanks were freezing when partially full.i wrapped and kept full.i kept adjusting igniter and thought that wastrouble but in back of mind knew better.then the symptoms changed when it would cycle and decide to re ignite it would woosh or a LOUD! Almost boom ignition.it startled me and probably would scare some.ok now some stuff to help you help me.it has a sight glass.i able to observe the flame it was blue no yellow.the blower puts out alot of air.a guy came as a favor to my brother and checked leaks and pressure ok.i ended up buying a eden pure heater and used the gas wall heater for that winter when i stayed.the following spring i pulled unit and cleaned nests debris etc.fan spun freely.i took a cover off of what i thought at thetime was part of fan/blower housing.found part of gasket missing applied thin film silicone noticed a section at bottom with gap that looked normal.well thru research now seeing a exploded diagram the gasket wasnt for a blower its for the combustion chamber and the part missing i thought looked normal is not!that gasket is supposed to be ca complete seal!so i need some good tips or advice reason being this is going to sound like a sob story lol.im very recently divorced and circumstances have me living in the camper this winter ugh!so i have the furnace to get working,im going to seal the windows and i have a new water heater coming to install!my income is seasonal now but found a source for parts for furnace.i know i need that gasket and might as well get igniter.but there was other stuff fairly cheap like gaskets for burner assembly? Limit switch? Im going to fill tanks monday and see about a big tank.probably pull furnace,order parts pending advice. Thanks to any of you folk for help i hope a furnace person sees this!