I've adapted a zoning damper for use in a cooktop downdraft system and just need some confirmation on principles of electrical components and any other feedback on this setup.

Kitchen downdraft system with external/outdoor blower unit. I installed a 24v transformer (wired to the 120 primary connections) on the line between the downdraft which controls the variable-speed blower outside. The transformer controls a power-open zone damper in order to keep the cold air from drafting in through the 8" duct between the outside blower and downdraft in the island when not in use. I am not real keen on electrical, and since this is out-of-spec for a zone control, I have two questions:

1) When the downdraft is on low, it supplies 80 volts the the transformer which steps down to 16 volts on the secondary connection to the damper motor. This lower voltage won't harm the transformer or the damper control, will it?

2) If the downdraft is started on low, the 16 volts to the damper only allows it to open about 10-20%. If I start the unit any higher than lowest setting it gives enough voltage to open the damper wide, and then if I turn it down to low the damper motor will hold it open. If I do this is there any chance of damaging equipment by supplying less than 120v to the transformer and less than 24v to the the damper motor?

Thanks for any advice here.