atwood water heater

What you describe sounds like a 110 volt heating element.

It helps the water heater recover quicker if using propane and electric or allows you to use electric only to heat your water.

So is this something that I can disconnect and drain system when I winterize. I don't want to damage it if I take it out.

What you MAY have there is an add-on heating element (Hott Rod ?), replaced the normal drain plug, and should have a switch to turn it on/off somewhere. Just where is/was up to whomever installed it. These are low wattage elements so won’t affect overall current draw that much. These elements are good for normal hot water usage, but as they are low wattage, takes a bit to warm the water to the set temperature. In which case you can have both the electric element on AND use the gas option at the same time.

As far as winterizing the wh you should be able to removed the element to drain the tank. Just make sure the power is off to the element.And of course, make sure there is water in the tank before turning it on.

Atwood should use a plastic plug for a drain plug. If there is an metal plug then the previous owner removed the plastic plug and converted to an electric heater element. The Atwood winterizing instructions are below. But in summary, remove the plug, flush out sediment from the bottom of tank, replace the plug.

1. Turn off your main water supply, that is, your pump or
   your water hook up source.
2. Drain your water heater inner tank. Upon doing so, you
   will note that, due to the location of the drain plug,
   approximately two quarts of water will remain in the
   bottom of the tank. This water contains most of the
   harmful corrosive particles. If while draining the unit, you
   note that it is flowing sporadically or trickling, instead of
   flowing steadily, we recommend one of two things. You
   should first open your relief valve to allow air into the
   tank and secondly, take a small gauge wire or coat
   hanger device and prod through the drain opening to
   eliminate any obstructions.
3. After thoroughly draining the tank, you should then flush
   it with air pressure or fresh water. If you elect to use air
   pressure, it may be applied either through the inlet or
   outlet on the rear of the tank. It may also be applied
   through the relief valve part. In this case, it will be
   necessary to first remove the relief valve support flange.
   In either case, with the drain valve open, the air pressure
   will force the remaining water, along with the corrosive
   particles, out of the unit. However, if air pressure is
   unavailable, your unit can be flushed with fresh water.
   Fresh water should be pumped into the tank either with
   the assistance of the on-board pump or with the
   assistance of external water either through the inlet or
   outlet found on the rear or the relief valve coupling
   located on the front of the unit. Continue this flushing
   process for approximately five minutes allowing ample
   time for the fresh water to agitate the stagnant water on
   the bottom of the tank and thus forcing the deposits
   through the drain opening.
4. Upon completion of the steps above, replace the drain
   plug and the pressure-temperature relief valve.
5. After this procedure, there will be approximately two
   quarts of water left at the bottom of the inner tank.
   Should this water freeze it will not cause any splitting of
   the tank.
   

I appreciate all the info here, on a final note, can I drain all the water from the tank and put the element back in over the winter months, of coarse its unplugged from 110 outlet, and tank is isolated from antifreeze. will it harm the element if its left in there.

You should put the plug back in if for no other reason than to keep spiders and other creepy crawling things out. Less likely during wintertime but you never know.