heated pad for the holding tanks?

mreric

have anyone installed heated pad to the holding tanks?   we are interested in doing some winter camping at areas were it would be just a bit close to freezing.     or any other quicker or better ideas ?     ( note that we do want to use the toilet and showers ) 

DougH

Dozens on the forum love winter camping or at least using their T@Bs for winter adventure:

Just use search feature on top right of desktop view to search for winter camping.

A couple folks mention they've tried the pads, and it worked fine for Bgkirk...  many more are trying it this year. 
 
https://tab-rv.vanillacommunity.com/discussion/comment/84737#Comment_84737

Some folks winterize and use the loo with RV antifreeze and shower with another water source then dump a bunch of antifreeze down the shower drain too in hopes that the mixture in the gray tank won't freeze when just below freezing occasionally.  I've done that with no prob so far.  

Others enclose the bottom of the camper and extend the Alde system to heat the tanks and drains for more of a four season camping result.  

I'm in the midst of doing just the heating pad and cable method, but don't plan to document the results for a couple more months.  But it raises a lot of questions.  Like if you don't enclose the bottom what kind of skirt will you use to keep cold winds away to reduce boondocking current draw?  And even if you can keep the gray and fresh tank from freezing at a campsite, what happens when you hit the road and there's 25F 60mph winds going across your gray tank valve and drain or that metal fresh tank drain?  Do you have to winterize again every time you hit the road? 

mreric

i think i am going to do the heated pad method as well,    they do have heated pad for the dump valve area as well.   i am hoping to add solar plus  with addition to the charge line from the TV should be able to keep up.   i hope...    

lkc001

Sounds great, but what are you going to do about the water lines that run under the trailer, all their elbows & the black & grey dump pipes & valves?

DougH

@lkc001 ; Cannot speak for @mreric of course, but I went with heat cable. 12V 15W/m self regulating variant that cannot overheat (fingers crossed). Carried at some plumbing supply shops in bulk, or you can get cut segments cheap on eBay. Eliminates hot spots and puts more power at the colder areas. Neat stuff. Tested first to make sure cable maintained various temperatures above ambient at 0.5-3.0A. Then wrapped drains and valves in aluminum foil as a conductor first, with windows in the wrap for the locations I attached the thermocouples directly against the PVC.  Then wrapped heat trace cable over foil at recommended twist rate (without approaching thermocouple locations) including some overlap on the drain valves.  Electrical tape to keep everything tight.  Sealed end of heat cable. Then added foam / foil insulation wrap (didn't want to mess with fiberglass), then a plastic tape wrap just for looks. Thermocouple leads go back to display units near the PWM knobs to control power to the three segments of cable.

P.S.  I am not a licensed plumbing contractor, but I do have YouTube. 

mreric

at this point i have to get under the trailer and see which elbow and pipe i have to protect,  the dump valve area is easy.     depending on how close i mount the pad to these elbow they might not need protection for my use.    i plan to use the trailer a near freezing temp.   but not much more.   this is just a precaution for me 

TNOutback

you didn’t state what kind of trailer you have, but I’ve peeked under the plastic undercover of our 400, and the water tank pickup line and the tank drain line would certainly need heat tracing.  They both are tapped at the tank drain and there is probably about 4 foot of line that needs protection.  I think if those lines are protected, I’m not so concerned with trying to heat the entire water tank.

lkc001

@DougH  I wish I was that handy!

DougH

@TNOutback ; Sounds similar to our 320 campers.  I had to put foil, heat trace cable, insulation wrap on 10.6 feet or over 3 meters of drains and intakes.  But you can get 4 meters of good self regulating heat cable for $25.  It's just time consuming to carefully whittle away the leads on one end of each cable segment.

I had eight thermocouple channels so used five in the basement.

• 15" Black Tank drain + twist + thermocouple

• 23" Gray Tank drain + twist + thermocouple

• 22" Clear tube inside to Fresh Tank

• 44" Blue pex inside to Fresh Tank drain + thermocouple

• 23" Blue pex / metal Fresh Tank drain

• Gray Tank heat panel / thermocouple / reflectix sheet

• Fresh Tank heat panel / thermocouple / reflectix sheet

In hindsight, enclosing the whole area and using the Alde extension, or blowing warm air from the cabin through a new airtight insulated basement box might have been easier.  But I was curious if a solar powered solution was possible.  Time will tell.

@mreric ; All that extra tubing is just to support the fresh tank.  If only protecting the black tank and gray tank drains and gray tank itself, your three heat panel approach should still work.