I have a Trane XE 60 Furnace and the thermostat sends the signal to ignite but burners do not ignite. What may be wrong? This just happened yesterday.

XE60 is just a model/style name. Locate and post the exact model #.

This is the model # TXCO36AHPAO

Is that # directly from the furnace? Sounds like an outdoor unit model #. Do you observe any action from the furnace (draft inducer, ignitor, blower)? Look for a diagnostic LED. If present, will streamline the scope of possibilities.