I have a Suburban SF-30 furnace in my camping trailer. It runs most week days during the winter so it gets a lot of use.
I have been noticing for a while that it struggles to light. It seems the worst when the thermostat is set to lower temperatures like 40F.
Recently, I had it apart to replace the blower motor so I blew out the nozzle to be sure it was clear. Since putting it back together it lite fine the first day and ran over night and all day at 70F. Then it set the thermostat down to 40F and let it run over night. In the morning it was out and would not light no matter how many times I turned it off then on again. Today I turned it on and off 5 or 10 times then it lit and went up to 70F and held it all day fine.
In summary, it appearers to struggle with lighting when the furnace is cold. Once it is warm it always lights nicely.
Any suggestions as to what I can try make it light more consistently?