The gas burners on my furnace do not ignite. When I turn on the heat at the thermostat and set the temperature to a setting higher than the room temperature I can hear a faint click within a couple of seconds. Within a few more seconds the blower comes on, but the burners never fire up. There is a LED light that flashes a consistent "code" of three short flashes followed by three long flashes. I assume this is some sort of error code, but have no idea what it means. I have checked and double checked all of the connection at the thermostat, which I recently installed, and have cleaned what I believe to be a sensor. The furnace has an electronic ignition pilot. It is getting cold outside and use of the furnace would be nice. Thank you for any help you can offer.