Protection from freezing

bobndot wrote:
Amazon has a 12v , 12”x18” tank pad @ 4.8 amps.


Would that be about 100 watts of heat ? ?

P = I * V or W = A * V
So, about 60W.

As an after thought, Winnebago probably used the most cost effective (aka cheapest) heaters they could safely/legally install.

Amazon has a 12v , 12”x18” tank pad @ 4.8 amps.


Would that be about 100 watts of heat ? ?

pianotuna wrote:
MDKMDK,

Any idea of the watts they draw?

Don, I have no idea. They're factory installs, but they had to be added by the Canadian dealer, after they received the unit from the factory. For reasons unknown, they could not be "factory installed" @ Winnebago. Cross border rules/regulations? Next time I'm under the vehicle, I'll see if I can see a label to identify them. My gray/black tanks are 36 gallons each, fwiw.
I did find a blog that discusses them in some detail, and mentions between 4A and 11A of current as a typical range. They link a couple of examples of after market add ons. Though they don't say, I'm assuming that's DC amps.
https://vancampinglife.com/when-should-i-turn-on-my-rv-tank-heaters/

pianotuna wrote:
MDKMDK,

Any idea of the watts they draw?

A good question, Don.

I found a link to the UltraHeat wepage that shows what size heating pads they offer and the amounts of current the different size pads draw. Note that the pads cycle ON and OFF under control of their built-in thermostats, so the current that the various pad models draw should be "way less", or at least "a little less", than the steady-state current values shown in the specs.

For versatility to drycamp or hookup camp in cold temperatures, I'd recommended using either the 12V pads or combination 12V/120V pads on an RV's tanks. Of course when hookup camping with only 12V pads on one's tanks, the RV's built-in converter should still supply plenty of 12V current for the 12V-only pads, so I really don't see the need for the combination 12V/120V pads in an RV ... the 12V-only pads should always be OK.

Here's the link:
https://www.ultraheat.com/ultraheat-rv-tank-heaters

If your tank heaters are 12 volt they’ll consume a bunch of battery amps.

MDKMDK,

Any idea of the watts they draw?

bobndot wrote:
My tank heaters run off 110v. Do all Navions run off 12v ?

Also carry a hair dryer to use in cold temps. Sometimes dump valves freeze .

Mine are DC only, with AC support/replenishment. Manual (Plumbing Section 7-14) states don't use them unless you're plugged in to shore/generator, or running the chassis engine while driving, or they'll deplete the batteries very quickly. I've got lithium, so I might get away with a bit longer standalone run time, but I'm not likely to test that theory any time soon.
If you've got tank heaters, they'll keep the dump valves operational, if the liquids behind them are warmed. Keeping the water heater "on" also helps prevent freezing of some of the adjacent lines/plumbing. I haven't got enough hair left to warrant carrying a blow dryer. :B

My tank heaters run off 110v. Do all Navions run off 12v ?

Also carry a hair dryer to use in cold temps. Sometimes dump valves freeze .

Phedley wrote:
We just bought this unit so there’s going to be a learning curve. That’s what I thought but I wanted to get more input. We will be plugging in but sure if holding tank heater will work. Thank You

The tank heaters will work fine as a safeguard, but they need a little DC "electrical boost". One of the weaknesses of the average class C is the tanks are usually exposed underneath the coach. As such, cold temps may affect them negatively. No definitive answer there, it depends on a few other factors, too.

We just bought this unit so there’s going to be a learning curve. That’s what I thought but I wanted to get more input. We will be plugging in but sure if holding tank heater will work. Thank You