I have a forced air, central air-conditioning and heatng system : Furnace: Goodman GMP075; Thermostat: White-Rodgers 1F80-261.

When I select Heat/Cool "Off " and set Fan on "On" in the thermostat, Air conditioner compressor fan located outside of the building is running but furnace blower motor is not running.

I need help: I want only furnace motor run to circulate air inside the building when I set "Heat/Cool" to "Off" position and set Fan to "On" position in the thermostat.

Is my thermostat wiring wrong? Or Is there any method to run the furnace blower motor only when heat/cool is set "off"? I have a copy of wiring diagram for the thermostat.

I would appreciate any help. Thanks.

Sungm