Fresh tank in cold weather

[Toy hauler guy]

I have a 2015 Dutchman Voltage 3970 with the all weather package.
My question is about the fresh water holding tank in cold weather. I have three tank heater switches for my black tank and two gray tanks. However, I do not know how I keep the fresh water tank from freezing up or is that a concern?
I spent last winter in the camper had a campground that had city water hook up. But I am currently in a campground that does not have city water hook up. So my freshwater tank is about half full and the temperature is dropping into the teens for the next few days.
I just don’t know if the freshwater tank will stay warm enough?

Thanks
Toy hauler guy

[persistent]

The guy who built it knows. Unlikely any other employee knows for sure.

There may be two heating pads on the two gray tanks that are wired to one switch. Were the switches labeled?

My tank heaters were installed by the dealer. The installer labeled the switches.

Typically, the propane furnace keeps the tanks and the pipes in the basement or belly from freezing. Tank heaters without the furnace generally do not keep pipes, valves and fittings from freezing.

Since you used the pipes last year without freezing, either the furnace kept them from freezing or some other heat source did.

A sealed and well insulated space can be heated by warm water tanks.

[Toy hauler guy]

Thank you for the reply.
On the control panel…..
There are three switches for tank heater. They are not differentiated in any way. I have a black tank a gray tank for the bathroom area and a gray tank in the kitchen area as well as the freshwater tank. So I have no way to tell what those switches are doing.
I did stay in the camper last winter and ran those three without any problems, but I was hooked directly to city water.

Thank you
Toy hauler guy

[dsol]

My trailer has the same three switches which are not identifiable either. I also assume they are for each holding tank based on many other folks assertions, but I have no idea and rarely hit freezing temps. I don’t like using if boondocking because heat generation generally requires a lot of energy and will drain batteries. Obviously, not an issue if plugged in.

I too wonder about the fresh tank in freezing situations but don’t have an answer. Agree with @Persistent, one of the more knowledgeable folks on this forum that residual heat from the furnace and trailer itself will help but no actual knowledge myself.

Good luck.

[persistent]

Of course most tank heater instructions say to not turn them "ON" when there is no liquid in the tank. And, of course, they are not needed for an empty tank. No freeze damage will occur.

So, how to tell what is going on in the fresh tank?

Measure the temperature of the water.
Measure at a tap nearest the tank.
The first water to come out tells the temperature under the sink.
The next water to come out tells the temperature in the pipe leading back to the pump.
Finally, the water from the tank comes out.
It may take as much as a quart of water to get to the tank water.

I consider 40 degrees F as the action point for my tanks. The tank won't freeze at 40 degrees, but it is time to do a little more observation.

I may use the low point drain on the fresh tank and measure the temperature there as a little water drains out. If I have shore power, I may switch the tank heater "ON".

If you wait until the water temperature is below 40 degrees and then switch one of the heater switches "ON" you can monitor to see if that switch causes the temperature to rise.

Tank heaters usually have a built in thermostat that turns "ON" at a low temperature. Mine is 40 degrees "ON" and 50 degrees "OFF". See the instruction manual for your tank heaters.

[persistent]

Originally Posted by dsol

My trailer has the same three switches which are not identifiable either. I also assume they are for each holding tank based on many other folks assertions, but I have no idea and rarely hit freezing temps. I don’t like using if boondocking because heat generation generally requires a lot of energy and will drain batteries. Obviously, not an issue if plugged in.

I too wonder about the fresh tank in freezing situations but don’t have an answer. Agree with @Persistent, one of the more knowledgeable folks on this forum that residual heat from the furnace and trailer itself will help but no actual knowledge myself.

Good luck.

I have two sets of switches for my tank heaters. One set operates using 12 volts. The other set operates using 120 volts. My 120 volt switches do not run from inverter power and so cannot work while boondocking.

With only 200 amp hours of battery capacity, I never run the 12 volt switches. I pulled the fuses to prevent accidental battery discharge. My propane furnace keeps the belly area above 40 degrees so I don't need the tank heaters when boondocking.

I measured the temperature in the belly and found that with the furnace thermostat set to 60 degrees, the belly temperature is 40 degrees. That temperature holds as outside temperature drops. I have tested it down to 15 degrees outside temperature.

[gsmyth63]

2015 Voltage 3990. My first experience in cold weather I turned on the tank heaters and just ran the fireplace. I also put heating elements in the air conditioners which I ran also. I had no issue with freezing.

[franktafl]

Originally Posted by persistent

I have two sets of switches for my tank heaters. One set operates using 12 volts. The other set operates using 120 volts. My 120 volt switches do not run from inverter power and so cannot work while boondocking.

With only 200 amp hours of battery capacity, I never run the 12 volt switches. I pulled the fuses to prevent accidental battery discharge. My propane furnace keeps the belly area above 40 degrees so I don't need the tank heaters when boondocking.

I measured the temperature in the belly and found that with the furnace thermostat set to 60 degrees, the belly temperature is 40 degrees. That temperature holds as outside temperature drops. I have tested it down to 15 degrees outside temperature.

I saw this the other day on an Rv that was permanently docked in Boone.