Heated Holding Tank

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Deputy
Posts: 16
Joined: February 22nd, 2020, 8:33 pm

Heated Holding Tank

Post by Deputy »

Hi All. My 2002 Chinook Concourse has a Heated Holding Tank switch. Have not paid it much mind since we do not usually travel when it is below freezing and the few times we did we had already winterized so I was not concerned. But now I am wondering about the “heated holding tank”. Is it the Black water tank or the gray water tank or the fresh water tank or all of them or some of them? And also, is it on a thermostat to only come on if the outside temperature dips to a certain level? And has anyone used theirs and have any thoughts ideas as to how effective it is? It could sure be nicer than traveling in a winterized rig with no water. Thanks in advance.
chin_k
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Re: Heated Holding Tank

Post by chin_k »

The fresh water tank is under the sofa, so if it freeze up, you are in trouble. The heated tanks are the gray and black tank. If you look under the rig, you will see the insulation around the tanks, and there is a heating coil under the insulation. Make sure it still works by either test for conductivity or turn it on and see if you feel the slight heat. I don't think it is meant for Alaska, sub-arctic environment, so it is not drawing a lot of energy, but you should keep an eye on it to make sure it won't trigger the LVD. I had to go thru it with tap to make sure it is not peeling off, since it is like 20 yrs old.
2000 Concourse dinette, on 1999 6.8L Ford E350 Triton V-10 Chassis
BobW9
Posts: 252
Joined: February 16th, 2018, 4:46 pm
Location: Full-Time on the Road

Re: Heated Holding Tank

Post by BobW9 »

My original heaters were placed on both gray and black tanks and also wrapped around one of the pipes (I think it was to keep the black tank outlet from freezing up, though I may be misremembering). Depending on manufacturer each pad probably uses 4-6 amps DC, so figure at least 8-12 amps continuous total in cold weather. In other words, if you're not hooked up to electric AC in the camp, then you better have a large battery bank or you'll likely run your batteries down over night.

Make sure the tanks are not completely empty, or the heat can melt the plastic over time (or burn out the pad). So run some water in the sink, and flush a few times, after dumping.

Also, on my Concourse the gray tank pipes have a trap under the shower that did not have any heating pad around it, and in cold weather (15-20 F at night and around 32-34 during the day, I think) that section of pipe cracked because of the water in it and had to be replaced (and it is in a very awkward position to get to). Since then, the few times I've been in below freezing, I dump some RV antifreeze down the shower drain to make sure that trap contains more antifreeze than water.

If its well below freezing, I also open the area under the couch where the fresh water tank is, and under the sink, to allow warmer air to circulate back where the fresh water pipes are (I took apart the area under my sink, so it opens to the pipes). There is not much insulation or warmer air back behind the shower stall, where the water pipes go, so I have been concerned they could freeze if its cold enough. This has not happened to me, I'm just being cautious.
2000 Concourse, Ford Triton 6.8 V10
chin_k
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Re: Heated Holding Tank

Post by chin_k »

Thank you, BobW9 for stating the current draw of the heater. I did not realize how much it is, and it certainly going to be significant for batteries.

However, I am surprised it is enough too melt the PVC. Do you know any antidote related to that? I would like to hear about it.
2000 Concourse dinette, on 1999 6.8L Ford E350 Triton V-10 Chassis
BobW9
Posts: 252
Joined: February 16th, 2018, 4:46 pm
Location: Full-Time on the Road

Re: Heated Holding Tank

Post by BobW9 »

Antidote? Just what the manufacturers instructions state - to keep water in the bottom of each tank, or damage to tank and/or heating pad may occur.

I believe the pads just have wires in them that get very hot, so if they contact the plastic of the tank without the water behind the plastic to spread out the heat and pull it away from the plastic, the plastic can get too hot. If the plastic is strong enough (or it is cold enough outside), then I'm guessing instead of the plastic melting, maybe the wires themselves can get too hot and melt the wire? Anyway, its easy enough to just run a bit of water and flush a few times after dumping.
2000 Concourse, Ford Triton 6.8 V10
chin_k
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Joined: June 26th, 2017, 9:38 pm
Location: Southern CA

Re: Heated Holding Tank

Post by chin_k »

I do not have the heating coil instruction in my Chinook folder. The previous owner probably lost it.

Yes, I got it now. It is best to follow the manufacturer instruction. Thank you, BobW9.
2000 Concourse dinette, on 1999 6.8L Ford E350 Triton V-10 Chassis
68camaro
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Re: Heated Holding Tank

Post by 68camaro »

My 2001 has the pads around black/gray tank but I have never used them sicne I only travel off-grid. I do winterize and during winter use bottled water for cooking/drinking and Antifreeze to flush toilet & black gray tank.
2001 Concourse XL Lounge model, 6.8L Ford E350 Triton V-10 Chassis.
Deputy
Posts: 16
Joined: February 22nd, 2020, 8:33 pm

Re: Heated Holding Tank

Post by Deputy »

Thank you all for the great information. I am happy to know those tanks are a bit protected if I find myself out when the temperature decides to dip below freezing. And thanks for the info on battery draw and antifreeze down the bathroom drain. Still don’t plan to be out in super cold weather but nice to know there can be protection if it is going to drop into the twenties over night. I note the feeder lines into the bathroom sink are in the outside cubby behind the spare tire. They are wrapped but the area is not heated. Perhaps a cause for concern.
BobW9
Posts: 252
Joined: February 16th, 2018, 4:46 pm
Location: Full-Time on the Road

Re: Heated Holding Tank

Post by BobW9 »

Yeah, those pipes for the bathroom sink are part of the system behind the shower stall that I was talking about - trying to get some warm air back behind there by opening up under the kitchen sink. When I was in real cold temps I even had my little space heater pointed so some of the hot air was directed under there (I had electric hookup, thankfully).
2000 Concourse, Ford Triton 6.8 V10
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