Suburban SF 25 FQ will not stay lit

[Rangerdaniel]

I have a suburban SF25FQ that is not working.

I have good battery voltage (over 13), connected to shore power. I have plenty of propane.

I turn the furnace on and hear the clicking.
Then the ignitor / electrode will light up, as I can see the blue flame through the little access window.
However, after 7 seconds the flame goes out. I can smell LP while the flame is lit. It will do this 3 times.

I have replaced the electrode, the gap between the electrode and the burner is correct, 1/8".

I have read a good bit about these furnaces, and unless I am mistaken if the furnace goes all the way to igniting the electrode it rules out issues with
the sail and limit switches.

Does anyone have any ideas as to how to troubleshoot this issue?

[Bama Rambler]

I would check the orifice and burner tube for a small obstruction like a spider web, etc..

[Rangerdaniel]

It looks very clean, but I have heard about running compressed air through it. I think I am going to try that next