blower problem

[steve mueller]

When i turn thermostat to the blower on position the AC compressor comes on .Makes no difference if system is in AC or heat or system off. Both AC and heat work properly. I just can,t run blower only by it,s self. Any ideas ? Thanks

[HayZee518]

there is a manual bypass for the blower. look on the plenum for a silver box with a white knob. pull the knob out. the blower will start.