Gas and Oil Home Heating Furnaces - Furnace Blower not turning on.

Burners working and heating normally, but blower not switching on after
the usual 30 sec. delay. Direct-drive blower turns freely.

Is the schematic stuck inside somewhere, like they do with clothes
washers?...don't see one. Don't know where the heat sensor would
be located for the blower. Don't have the make/model as yet, will
add later. Guess it's at least 15 yrs. old. Beige color.

Would also like to know how to adjust flames properly...I think it's
mostly blue flames, slight orange on tips?. I shut the gas off, so will
need to know how to light the pilot.

Do you have AC on the furnace? Will the blower run from the tstat. After The burners are on does the blower hum??If you give it a push does it run???
the schematic should be on the blower door

G20Q3E-75-2 Ser.# 5891L07111

I'm going to check for AC tonite on blower, but I doubt that there is AC.

Also the cap....could be a run cap, not a start cap maybe?. Run caps
have a much smaller mF value than start caps.

Primarally interested in the thermal switch circuit that turns on blower.
Guess I'll trace the wires back from the motor and see.

Most fans on gas furnaces today do not use a thermal sensor to turn on the fan. The fan is usually controled by a timer on a circuit board.

I found the manuals hiding in the door, followed the troubleshooting
chart, found no 120 blower voltage, but 24V good. Said to replace
blower control board....I don't think so!, so I looked at the solder joints
on the foil side, one bad joint on a relay...works fine now :)

Thanks to all