I am working on an older a/c unit.The heater runs fine.Blower comes on in the on position.a/c outside unit comes on in the a/c auto mode but blower doesn't come on.Initially one of the wires was touching another lead on t-stat.replaced t-stat and the transformer.Now I think its either the sequencer or a relay.Are there two different relays or sequencers ,one for heat and one for a/c or do they run off the same one>?HELP! Or I could get fired---JK and thanks!!