View Full Version : How to correctly hook up fan only mode???

05-03-2012, 01:48 PM
I have an ultra 3 80 furnace by Armstrong air conditioning Its from 1992 it was originally wired where the fan will only kick on when the heat kicks on I would like to make it run when I turn the thermo fan switch to (on) so I replaced the two wire cord with a 5 wire
On the thermostat I have (o/b),(y),(r),(g),an (w) now on the furnace blower board I have G,W,C,Y and R
I have connected w and r because those are for the furnace to kick on and then I connected G this is supposed to be for the fan to kick on or off . When I turn the thermo fan setting to on a relay buzzes on the board and the blower acts like it doesn't have enough power to turn completely on I'm not sure what else to do or check any ideas?!!!