FW28z, you were correct about the furnace....I called Atwood with the model number and they confirmed there is only one speed for the furnace
I tried all the other positions, and High/low speeds work both in the "fan" and "cool" position. so all is good.
I guess I will leave the water heater for the warranty work, can't find any bad fuses or breakers, and looked around inside the front cover of the water heater but did not see any thing out of place...loose wiring or anything. Its OK, the gas position works fine for now.