Furnace off Heat Pump for garage

[Aruba1]

I have a heat pump that we removed due to a faulty compressor. The furnace itself it in good working order. I would like to connect the furnace to heat my garage and install a termostat. Does any know if this can be done or are they designed to work as a combined unit. Just looking for good advice from this forum that does not include "search the yellow pages for an electrician" .

Thanks in advance.