Trane Xb Furnace Not Heating

We have a trane xb furnace that is not working properly.

Trane xb furnace not heating.

I went ahead and replaced it with the spare we kept careful not to touch the ceramic end. I have a trane furnace x b 90 model number tuc 080c942b8 the problem i m having sometimes the furnace blows cold air then i go down and check and find the trouble code was number 2 then it locks out external lockout then i reset the furnace induce motor starts then the pressure switch closes the flame igniter starts glowing it seems like the gas valve not going on long enough. Check out these common troubles and possible solutions. If it seems like your trane furnace just isn t heating your home as effectively as you want then the culprit might be a lack of airflow making the first step in repairing a trane furnace checking your filters for blockages.