Black tank freeze up- Help!

[tornado-bait]

I am quickly realizing that there is much more info here that is NOT in my manual. Anyways, as I come accross all the problems I created by towing my rig thru -22 Nevada, I am gathering knowledge for the future.
I got all the water lines and grey tank unfrozen, but the black tank is a problem. The sensor says it is empty but it is backed up into the toilet. I have been trying to get some hot water up into the drain pipes under the trailer, but I am not having much success. I am at Tiger Run resort in Breckenridge CO, so the temps don't help.
Also, when I was running the water in the bathroom sink, the toilet backed up more. What (horrible?) situation would cause that? That sink is linked to the grey tank, at least in the manual. That sink drain seems blocked as I don't see it run out the grey water valve while running the water.
Lastly, is there a good source for lots of info on winter travel and living? All those questions I should have asked before!
Thanks, David

[tornado-bait]

One more question: someone at the RV park said to pour sidewalk salt into the toilet. Safe?

[2airishuman]

hi t'bait

how's the skiing?

part of the issue is determining if it's FROZEN or otherwise blocked with solids.

if it's truely frozen, you'll need to thaw it, i don't think adding salt or anitfreeze will help much.

now if this is more of a solids problem (from being parked a long time)

here is a thread that may help...

http://www.airforums.com/forums/f444...ank-31189.html

or this one...

http://www.airforums.com/forums/f446...ght-34456.html

ultimately u may need a sucker/pumper honey bucket truck to make a visit and get things moving again.

there is an entire section on winter living, and some of the threads are just chilling!

http://www.airforums.com/forums/f462/

as for the blank tank rising with your lav sink...

some are plumbed this way, regardless of the owners's manual

OR u could have the 3 drain values turned such that the gray is backing up into the black...

now regardless of how u fix it, PLEASE POST PHOTOS of the process and outcome...

i can't understand why noone takes me up on this last request.

2air'

[dwightdi]

Once the big drainage valves and pipes leading to them are frozen there is little hope of unfreezing them without wrapping them with the heater tape used for that purpose and waiting for better weather so the tape will work. If all else fails, you could skirt the trailer and rent a salemander heater to blow hot air under the trailer. I used this technique to unfreeze the plumbing on a crawl space under a house. It most likely would be less costly than paying an RV dealer to bring it into his heated shop to unfreeze it.

[thecatsandi]

You are going to need to get the tank warm, as well as the drain lines. Salt may work but it will take a loong time. if you decide to try anti-freeze make sure you use RV anti-freeze. If you use Auto Anti-freeze you risk a BIG fine.

[HowieE]

At -22 degrees you most likely froze the tank rather than haveing a solid blockage. The best way to thaw it is to get it inside.

There is no value to the insulation Airstream installs.They use blocks of foam placed around the tank with no means of completing the insulation at the joints. Much like insualting your house and leaving the windows open. This means the insulation is just a waste of time.

[fotochop]

Originally Posted by HowieE

At -22 degrees you most likely froze the tank rather than haveing a solid blockage. The best way to thaw it is to get it inside.

There is no value to the insulation Airstream installs.They use blocks of foam placed around the tank with no means of completing the insulation at the joints. Much like insualting your house and leaving the windows open. This means the insulation is just a waste of time.

Sympathies For Your Solids, t-bait. In light of the above (crazy design, I agree) do you guys think it would help to add non-expanding foam between the styro panels around my black tank (out of the unit now) upon re-installing? (at -22 it's probably all just p-in' in the wind, no pun intended..) Someone needs to market an expandable 'heat-skirt'...nevermind..we do it all ourselves anyway... good luck!

[clancy_boy]

My only thoughts are if you thaw the unit out and are not in a location where you can dump it easily then you may be in for one big surprise. Freezing usually involves some expansion of the liquids. There may be some cracks in the plumbing when you thaw the system out. Being indoors may be a bit messy - I for one don't want to see photos but if you post them I may peek at them . Can you skirt the unit as others have suggested and pump heat under there? I recognize that you are in a cold location and that may not ne easy. You only have to raise it a few degrees for a short time to melt the mess. Good Luck......

[Bambi_Bandit]

Originally Posted by tornado-bait

Also, when I was running the water in the bathroom sink, the toilet backed up more. What (horrible?) situation would cause that? That sink is linked to the grey tank, at least in the manual. That sink drain seems blocked as I don't see it run out the grey water valve while running the water.

The newer 28' floorplan (post 2002 or 2003 I think) all have separate grey/back tanks, as opposed to the single large black/grey combo they used to used earlier.

However, that being said, when Airstream put the the separate black in, the bathroom sink drain is set to drain in the black tank. The kitchen sink and shower are the only ones that drain to the grey.

May be a bit late now, but I used to wrap my drain valves with electric heat tape and wrapped it with insulated foam tape. Plugged it in when the weather was near freezing or would freeze.

That may help thaw the drain valve and elbow that is currently exposed. If you can crank up the heater (not heat pump) and get heat onto the tanks, and use the heat tape to thaw the valve(s) (sounds like black is the only one frozen) you should be able to dump in a few hours, depending on the ambient temperatures.

[HowieE]

Originally Posted by fotochop

Sympathies For Your Solids, t-bait. In light of the above (crazy design, I agree) do you guys think it would help to add non-expanding foam between the styro panels around my black tank (out of the unit now) upon re-installing? (at -22 it's probably all just p-in' in the wind, no pun intended..) Someone needs to market an expandable 'heat-skirt'...nevermind..we do it all ourselves anyway... good luck!

If you want any level of integrity to the insulation on the tanks then YES you would have to seal them 100%. A truly fully insulated tank with liquid in it would significantly extend freezeing time. The more liquid is in the tank the longer it would take for the valve area to freeze because of the ajacent thermal mass of the water.

The problem he currently has is the the valve, the area most exposed and with a smaller thermal mass than the tank, is frozen and thus precluding draining. Most plastics are somewait forgiving to the expansion that occures when ice thaws. However the valve assemblys tend to be of a harder type plastic than the tanks and thus may crack during thawing. Heat should be appled slowly. If you skirt the trailer and use a heater don't put the heat directly on the valve.

[InsideOut]

Originally Posted by tornado-bait

I am at Tiger Run resort in Breckenridge CO, so the temps don't help.

You may want to hook-up and drive down to Denver today...it's 62-degrees! Although another storm is expected to blow in this evening...and last through tomorrow. It's less than a two hour drive...

Shari

[87MH]

Originally Posted by tornado-bait

I am quickly realizing that there is much more info here that is NOT in my manual.....is there a good source for lots of info on winter travel and living?

Heere is a link for a holding tank heater - don't know anything about it...

RV Holding Tank Heater on Sale

Thought the knowledge of it may be of some importance to those of you who are not as temperature challenged as I am.

[pmclemore]

I'm with Shari with one additional suggestion: Since your tanks are so full, they're sloshing, I think you need a pump-out down from your john.

Then head for warmer climes - then find a big parking lot and find a sunny spot you can hover over.

Good luck - you've had a pretty good run-in with misery.

Pat

[tornado-bait]

thanks for all the great advise and links to winter living. The tank thawed on its own afterall. We had one day of 36 degree weather and sun and that un-did it. Phew!
I am now installing the heat tape and insulation. Was curious as to the post on keeping more water in the holding tanks, rather than empty. I do let the black sit, but have been keeping the grey completely empty. Both valves do freeze up each time though and I haven't emptied the black since.
What exactly does a holding tank heater accomlish? Is it something that would help on a newer trailer like mine?
thanks, David

[nunya001]

David - Tank heaters are essential in genuinely cold weather. do a search there's a ton of info here, also you can check the winter living forums - very good info

[HowieE]

The reason for keeping a quanity of water in the tank is because the larger quanity of water has a higher thermal mass and thus takes longer to freeze. This is not a CURE-ALL as it will only prolong the freezing time not eliminate it. Good for an overnight situation were the temp is falling below freezing.

Leaving the gray water open during freezing temperatures is fine as any water will flow to the camp ground sewer before it can freeze. However the valve assembly will most likely freeze open do to the small amount of water that will remain in the valve groove.

If you install heat tape to the valve you will have to overwrap it with insulation to make sure the heat is applied to the valve and not just dissapated to the surrounding air. Also if you wrap the valve area tight and back to the tank the heat of the tape will flow towards the water in the tank. Heat in water will flow upwards.

[Silvertwinkie]

I'm a little late to this thread, but my question is:

Did you have the furnace running? All Airstreams have some sort of tank heat, be it forced air or on the 22s, electric. If it were well below zero, I'd consider running the furnace while in transit. I don't think that practice goes against the design or engineering of the furnace, but it may solve your freezing issues.