Hello,
I have a York Diamond 80 furnace that was installed new in 2001. My problem is that the Heat exchanger will not fully light and stay on. The ignitor works fine but when ignition begins only the two burners closest to the ignitor ignites. The two will burn for a few seconds then go out. I can't figure out why all the other burners don't ignite when the 1st two do.
If I remove the front panel they will all light up, always it seems. Why? Is there not enough air getting in there with the door panel on. Also I noticed the if I blow on the two ignited burners all the others will light up. Once they all light up the furnace seems work okay until it comes time to cycle on again.
I have replaced the temp sensor and think the igniter is probably okay since it does ignite the two burners closetes to it. Why would the fire not spread to all the other burners unless I blow air around them or remove the door panel? Why do I always get the weird ones?
Thanks for any help anyone can provide. I have had techs out here over the last few years that can't seem to permanently figure this out.
Do I need to buy a new furnace?

You do not need a new furnace but you do need to find a service person that knows exactly what they are doing to correct this situation. The furnace needs to be serviced and at that time the service person will have the proper tools to set and adjust the burner if necessary. The reason I say this is because the burners are not jumping across so they all light at the same time and that is not good.

Thanks but you didn't provide any possible solutions beyound what I have tried. Have it looked at by a professional...
The installer was/ is pretty reputable, he is the one I have had out servicing the furnace since new. He thinks there may be some inherent problem with the heat exchanger.
What may be the top 3-4 reasons that my be causing this? Anyone?

There could be many different reasons and I did not list them since I felt you may not have the tools or knowledge to do the testing.
If you have a manometer check the discharge gas pressure and make sure it is within spec for starters. They look like these below.

Then with that done you might pull all burners and clean the heat exchanger/burner tubes/etc. Pay attention to any jumpers on the burners that might be bent/dirty/or rusted and replace if necessary.

NOTE if the person that has been servicing your unit since new fells that there is a heat exchanger problem why did he not test it?

Post back with results of your work.

Well I finally figured things out and fixed the problem with is York POS
I replaced it with a new Lennox.