I recently installed a xv95 Trane furnace and I'm having problems getting the burners to light. I checked the inlet pressure and I have 7" wc. I removed the gas valve and manifold and checked for anything that could be plugging them. I found nothing. The flue pipes are 3" pvc (required for 120000 btu) and are about 8ft long with 1 90 and 1 45 on each pipe. I checked the wiring coming into the furnace to confirm the polarity was correct.
When I send a signal to start the heat the inducer fan comes on and the furnace goes through its start up procedure. Then the Hot surface ignitor comes on the only burner that will light is the one on the right at the hot surface ignitor. It stays lit for about 2 seconds then it shuts off.
I have pulled the burners and confirmed that they were ok. Found no problems. Anyone have any ideas?