Furnace problem

I used mine only once the spring I bought it, then that fall it would not light on our second trip. The dealer took out the furnace and took it apart and it was full of RUST! Yep, the first time we'd used it, it had burned the paint off of the inside which contributed to the rust and dust inside it. He used an air hose to blow it out, re-assembled it and it has worked fine ever since. Says he gets at least 10-12 every fall for the same thing. When fan kicks on, it will not light and time out. You can hear it trying to light but had sounded like it had very low pressure, not the forceful 'swoosh' you normally hear when trying to light. It's because it is blowing around so much rust/dust particles.