DGATO75BDD Having issues

[WADE]

Hello, was wondering where you would get the fault codes for this furnace it appears to be flashing just once. Last night went to my brothers cause he was having issues with this furnace it was not heating it has a programmable thermostat and when he got there it kicked on for a minute then kicked off and would not restart. I went and reset the switch inside the furnace(without thinking about the flashing codes) and it turned back on and started to light and the little blower started running as usual it started the normal heating and ticking then the blower kicked on and thought it was ok, but wasnt blowing heat from vents then it shut back down. I reached up and felt around the flue and was warm but not hot could actually touch it. Then I think it restarted on its own (I might have done something but dont remember for sure) and worked ok this time and I went home after about 20 minutes. when he got home tonight same thing he said it flashed once every 5 seconds or so then i had him restart it and it is working ok far as I know as this was about 20 minutes ago. Any Ideas?

[Mark]

I believe one flash signifies an ignition failure. To me it sounds like it could possibly be the flame sensor. That is the L-shaped wire with a white ceramic sleeve on the burner. I would try to clean that sensor. Here's more: http://www.mobilehomerepair.com/TechTip1.html

Mark