When I turn on the thermostat to "cold", the fan outside turns on and the condenser gets cold, but the blower motor will no kick on inside.

However, if I turn the thermostat to "heat", the blower kicks on inside and it blows out hot air.


What might be causing the blower motor not to come on for the a/c?


Thanks

The thermostat controls the fan in AC mode usually. I'd start with thermostat configuration, if any, and trace the G terminal at the thermostat. G to Rc/R will make the fan com on, so should the fan switch on the t-stat.

The AC also uses a higher speed.

I don't have a "fan" option on the thermostat, just "on" and "auto".

The A/C and thermostat have been working fine for the two years I've been living here. Now all of a sudden it won't kick on inside.

So would I still need to look at the configuration or is it probably something else?

Right - ON should turn on the fan right away. AUTO turns it on with the AC.

The heater uses the heat in the plenum or time to activate and de-activate the fan.

There are lots of options, but we are both in the dark here. That's about all I can say without knowing more. Don't even know anything about your furnace or how old it is.

I don't see a name on the unit in the attic, but the one outside says it's a "Inter-City Products" 1992 is the manufacture date.