Heating the water tank.

daleandwendy

I may run into cold areas in my future travels and came up with an idea to heat up the water tank to prevent freezing. I have a 2017 S Max. Under the sink is a PVC pipe which I believe is the "pour in" inlet for the water tank. I would connect a battery powered garden hose timer to periodically send hot water back to the tank when I'm traveling through freezing areas. The tanks are enclosed under the trailer. My hope is that the radiant heat would keep the grey and black tanks from freezing. I would appreciate any thoughts about this theory or ways to improve on it. 
Dale



Moderator's note:  Photos have been resized.

Dalehelman

Not quite clear on your idea. The black water tank is directly under the toilet. The gray and fresh water tanks run  parallel to the frame rails and are covered by a  corrugated plastic sheet. The parts most  susceptible to freezing are the 1 1/2" gray water drain pipe and the 3" black water drain. So heating the area around the tanks would probably not be  sufficient. Hope this information helps.

Verna

This is a photo of a T@B "under construction" in the production line at NuCampRV this summer.  As you can see, there are blue and red water pipes running along the front wall that are not visible, nor accessible to the owner. These would not be able to be protected from the cold.  

Dalehelman

Verna said:

This is a photo of a T@B "under construction" in the production line at NuCampRV this summer.  As you can see, there are blue and red water pipes running along the front wall that are not visible, nor accessible to the owner. These would not be able to be protected from the cold.  

Verna do you know if the front wall is the same as side and top in thickness and insulation?
By the way great picture. Do you have any others  showing our trailers under construction?

Verna

@Dalehelman, the front wall is the same thickness and insulating factor as the side walls, with the exception of the exterior covering.  

Just in case you're curious, the contraption connected to the water pipes is putting pressure through the pipes to check the integrity of the connections. Also, this is the new 2017 3-way fridge with the exhaust hoses comes out of the side walk, not the front wall. 

Yes, I do have more photos from Mike's and my production floor tour by Joe Mullet, the founder of Pleasant Valley Teardrop Trailers this summer. There's that resizing task, so posting resized photos is not going to be done this busy week. Maybe when I'm babysitting the emu the week before Tabazona. 

daleandwendy

Thanks Verna for the T@B anatomy picture. My intentions are to copy this idea from another post using heating elements for the tanks and exposed pipes, and possibly adding a valve closer to the grey tank.

http://tab-rv.vanillaforums.com/discussion/480/tank-heating-pads-installed-by-anyone

I can easily circulate hot water into the fresh tank to keep it above freezing or make it extremely hot to keep the enclosed area warm.  Or I may have to add heating pads to both the black and grey tanks. By the looks of the picture you posted, I think the internal plumbing will be safe. My wife requires a 75 degree environment and i can leave the pump access door open. I may have to take off the underside cover to see what's under there. I could add tiny fans to circulate the heat. And maybe make the compartment more airtight. 

Ratkity

Keep in mind that it's the hot water lines that freeze first - something to do with supercooling and physics. As soon my geek friends started discussing the equations, my brain cell shut down. Might want to look into that before doing a hot water circulating thingie.

TabberJohn

This Roadtrek Class B blogger posted this unusual mod: http://roadtreklife.blogspot.com/2016/03/rv-hot-water-recirculation-system.html

tjandtab

I to have thought of a way to keep fresh tank heated above freezing by recirculating hot water from Alde though fill vent to above freezing. some problems to ponder Alde not working correctly under way on LP, where to incorporate a 12 volt thermostat at coldest waterline point, hooking up a 12 volt electric water solenoid valve, tank would need that same venting while hot water was being recirculated, would need a dedicated return water line back to tank and trusting it all while bouncing down the road. But I think it could work. That is how the on demand water heaters on bigger RVs keep themselves from freezing

tjandtab

Ok one more thought install a T fitting between hot water line under sink and white pvc fill tube with the 12 volt solenoid valve between the two wired to the water line 12 volt thermostat circuit that would recalculate hot water back to fresh tank. Opens solenoid valve just above 32F and heat fresh tank to maybe 45F ?