2017 Newmar Baystar

I think you will find that hose only lets you pump RV antifreeze into the water lines. Usually, to sanitize the fresh water tank you need to pour bleach into the fresh water fill inlet. I haven't seen any RVs where the pump is able to put water into the fresh water tank. The valve associated with that hose most likely only allows selecting the hose OR the tank as the liquid supply to the pump. Isn't that second valve just a drain (to the ground) for the plumbing in the wet bay? To winterize, you first have to change the water heater lines to "bypass" so you can pull the heater plug and drain it. Without that bypass, you would have to fill the entire water heater before the lines got winterized, requiring gallons of antifreeze. Don't forget the icemaker line!

Hi Mike,

I do not have a Baystar, but I have a Newmar, and I think the items you are asking about are the same.

The valve you are not sure about prevents the water pump from pulling from the fresh water tank. When you close that valve and open the one on the winterization hose, you create a new source of liquid for the pump to pull from.

When you are sanitizing, you want your fresh water tank fill valve to be open, with the other valves positioned as just discussed. That puts your sanitizing solution in the fresh water tank.

When winterizing, turn the fresh water tank fill valve to the closed position. This prevents your antifreeze from going into the fresh water tank and directs it to the plumbing system throughout the coach. With the tank drained, there is no reason to put antifreeze in there.

I also bypass the water heater when winterizing, although some do not. The water heater bypass valves are located behind the water heater, usually accessible via a cabinet door under the sink.

There is a Youtube channel by RVGeeks that has numerous videos I have found helpful with Newmars. They have one that specifically speaks to winterization and would be worth your while.

“and add sanitizer to the fresh water tank.“

Have you any experience in sanitizing an RV fresh water system? The most used sanitizing agent is bleach diluted to a quarter cup for every 15 gallons. Then you rinse the system. Get experienced help the first time to avoid any trotting.

Thanks Gary for your reply. I have bypassed the heater already. I have also been able to draw water up into the winterize tube to see is it would go. I am just not sure if switching the two valves sends it to different places. In my previous Class C we could unscrew the overflow valve in the top of the tank and add the solution.

Thanks Shot-N-Az. That makes perfect sense. When I was trying the other day I think the main problem I may have had was that I also had the water connected to the rig. So when adding chems I should have "fill tank" open and when winterizing I should have "city water" on? Don't know about your Newmar but our Baystar has the Tank/city valve in one bay and the pump and winterizing hose in the next. Wish it was all in the same bay. Found the valves for the water heater under the sink in the rig. May just have to spend the $100 to take it down and let a tech show me how. Our Coachmen was a breeze as everythoing was in one hook up with labeled valves. Thanks for your help.

Lwiddis. I have had experience in this but we have only had this rig a couple weeks and it was left to me by my sister so no verbal "how to" talks. When we go on long trips I always like to fill the fresh water tank half way to always have water if needed. We use Camco TastePure Drinking Water Freshener for RV and Marine Fresh-Water Tank in the tank to keep it from going stale.

Thanks again Gary for the tip on the icemaker line. I do have to figure out how to get to that and either turn it off or bypass it. I think there is something about that in the owner's manual.

Hey Shot-N-Az . Maybe you can answer this question for me. In the bay where the Tank/City Water valve is there are two lines running down the back wall through the bottom of the bay. There is a label next to them saying "Low Point Drain" Are these the overflow drains for the fresh water tank? The valves were closed when we brought it home.
P.S. they are right below the fresh water tank.

You should see two low point drains...one hot, one cold. Those will drain your plumbing. The fresh water tank has its own drain. You have to reach through the wet bay to find it. I’ll see if I can take a pic and load it here.

I don’t seem to be able to load a picture here. I’ll email it to you.