I have a Lennox Hs16-261U-4p Air Conditioner. It worked fine last summer. I turned it on today and it starts right up. However, the fan in my RHEEM furnace is not coming on. It does not work on the auto or fan setting. The furnace worked fine all winter long. I am told the AC unit may need to be reset. Is this a possible way to fix it and how do I do that? I do not see a reset button on the outside.

I have a Lennox Hs16-261U-4p Air Conditioner. It worked fine last summer. I turned it on today and it starts right up. However, the fan in my RHEEM furnace is not coming on. It does not work on the auto or fan setting. The furnace worked fine all winter long. I am told the AC unit may need to be reset. Is this a possible way to fix it and how do I do that? I do not see a reset button on the outside.

Usually there is a relay in the furnace that will activate the blower when the outside A/C unit comes on. Look for the relay OR if it is on the circuit board (if so equipped)
You might have to replace it. Look on the wiring diagram located on the inside of blower door for the location of the fan relay.