Frozen black water - RV-Dreams Community Forum

Lucky Mike · RV-Dreams Family Member

Frozen black water

sunflwrgirl · RV-Dreams Family Member

We are thinking that the Black water tank has frozen since it wont drain but just a tiny bit. We even tried to fill it reverse style but it did not work. Im wondering can we pour something like Drano or even to go so far as like an anit freeze. Or do we need to just wait for them to thaw on their own? I also did pour a large bowl of hot water down the toilet as well to see if that helps and it did not get us where we need to be.. ;)

Lucky Mike · RV-Dreams Family Member

the Dawn has nothing to do with it......

anytime the temp dips below 32 things freeze.......you either have to skirt the coach or you can pour a half cup of antifreeze or wiper wash after using .....this will keep it from freezing .

if the temp drops below freezing (32 degrees ) and the wind is blowing you also have a wind chill factor that will speed things up..................I always skirt my unit or at least the tanks in areas with low temps.

you can purchase remote temp units (indoor outdoor thermometers) at walmart cheap and some have alarms on them that you can preset the temp................these come in pretty handy to know to either skirt or pull valves bad weather is coming

(NOTE:)

most freeze ups occur on the valve line after the tank closer to the pull valves do to there being exposed to the elements

-- Edited by Lucky Mike on Sunday 24th of November 2013 08:51:29 AM

SnowGypsy · RV-Dreams Family Member

DO NOT put Drano or any chemicals into the black water tank if it is not draining. I would never, ever put Drano in any RV tanks. I wouldn't pour anymore hot water down there either since if it is cold and you are pouring the water on a block of ice, it will freeze just making the situation worse. Are you located where the temperatures have been below freezing? I'm guessing you have no tank heaters and did not use any anti-freeze in the tank previously. They do make an anti-freeze for RVs, pink stuff and even Wal-Mart usually carries it. When we were in freezing temps, we put small amounts, probably a cup or two in the holding tanks and drains on freezing nights. Maybe someone else has an after-the-fact solution for you but try not to make it worse. Here looks to be a good article from the RV Doctor: www.rvdoctor.com/2012/02/frozen-rv-holding-tank.html

GENECOP · RV-Dreams Family Member

Now that it froze your best bet is to wait it out, let it defrost on its own....

sunflwrgirl · RV-Dreams Family Member

We are in El Paso Tx. The weather was 37 yesterday and got to around 31 last night. We did not put any more hot water in there and will not place any "caustic" things in there either. :) Really not understanding why it is freezing like that this year when last year it never did that. Only thing we have done differently this year is I am using a mixture of dawn dish soap for the black water tank recently as opposed to the RV drop ins.. Does the drop ins help to keep things from freezing? Also is it wise if we just leave the black water open or should we keep it closed till it all thaws and can take everything out with it?

bjoyce · RV-Dreams Family Member

"Also is it wise if we just leave the black water open or should we keep it closed till it all thaws and can take everything out with it?"

Keep it closed.

sunflwrgirl · RV-Dreams Family Member

Thank you everyone for your help. But just need to be clear about something. So after we do get it drained then we can put anti freeze or windshield fluid in it (about 1 cup) and it will help keep it from freezing?. Is that with still using the dawn or should we not add the dawn no more.. We have looked over the weather reports and it seems that after today it should get warmer again (50's), so this is good..

SnowGypsy · RV-Dreams Family Member

How much dish soap are you putting in the tank and why? The only thing I would be putting in the tank is RV anti-freeze not any other concoctions since you could mix the wrong chemicals and create toxic fumes. Most soaps, having fats, become globs of gel when they get really cold and I'm think that won't help your situation. I would also think about flushing the tanks really good before putting in the RV anti-freeze to clean out solids that might be remaining behind.

Terry and Jo · RV-Dreams Family Member

I may be wrong here, but with a holding tank in the underbelly, it is somewhat protected from the cold. Since you said the low was 31 degrees, I'm suspicious as to whether the tank is actually frozen. I can't speak to why you're only getting a little out when you pull the black tank valve open. You might have other issues than freezing.

We are living in our coach full-time here in Oklahoma City. Even when our temperatures got down as low as 14 degrees, I've never seen our underbelly get below 40 degrees. To some degree, the underbelly is warmed by one of our furnaces. (Our Mobile Suites has what is called the Canadian Package, which includes two 30,000 btu furnaces instead of just one for the whole coach.) If you are running your furnace, it should be helping keep the underbelly warm.

To monitor temperatures in our coach, we purchased a Radio Shack wireless remote thermometer with an extra remote sensor. We keep one sensor outside under a slide (out of the sun) to monitor outside temps and we have a second one in the underbelly near the water manifold area. The inside unit cycles through the sensors showing each remote sensor's temperatures. This lets us monitor our temperatures and is really handy. I just need to remember to get the outside sensor in before we try to travel. I missed doing that once and lost the sensor. Unbelievably, I later found the sensor near our mobile home park and it is still working today.

Should the wireless thermometer interest you, here is a link to a blog posting that I did about ours.

Technology is VERY Helpful

Terry

igotjam · RV-Dreams Family Member

Terry is correct. At 31 you should not be freezing the tank.

sunflwrgirl · RV-Dreams Family Member

OK, then possibly it is the dawn soap causing our problems. One we are able to drain it, then we will flush it obsessively as we do often. Lol then we will purchase some RV antifreeze and use that instead. Hopefully it is just a matter of being frozen. It seems to be the only thing that makes sense to us since we are very good about flushing the system at least every other time we drain it.. At that we flush it multiple times till the water is basically clear...

Also you asked how much Dawn are we using.. I was using about 1/2 cup. But honestly only started about a month ago as I have seen some folks post on here that they do as well as another couple here in the park has mentioned they do it. Maybe its best to only do that in the summer months and not the winter :p

Can someone tell if Walmart carries RV Antifreeze, or is Camping world my only option?...

dewwood · RV-Dreams Family Member

Like Terry said, if it only got down to 31 and then warmed back up, I doubt that you are frozen up. I would more likely suspect some form of blockage in the black tank or your valve on the black tank is not opening. that could be caused by the cable coming loose. If you can not trouble shoot the problem yourself you may need to contact a mobile rv contractor or take your unit to a repair facility.

SnowGypsy · RV-Dreams Family Member

Yes, your local Wal-Mart should have the RV/Marine Antifreeze. Some of those quickie auto parts stores also carry it.

Right now, at 12:07 pm it is 31 degrees with a wind chill of 25 degrees in El Paso. They are having unusually cold weather. That is enough to freeze the tank especially near the outlet area. We always kept anti-freeze in our tanks but we did have the valve freeze shut in temps about equal to this. We are very familiar with being in winter temps in an entry level trailer. A lot of people run electric heaters, especially if the cost of electricity is included in their site fee, and without the furnace running, you can be pretty sure that the tanks will freeze and another bummer is that if you don't keep the cabinets open, the inside water lines will freeze. How close you are to other RVs plays into the equation also since there is more warmth in a cluster. When it is cold like this for 2 or 3 days, you can develop a large ice cube in the tanks. We encountered unusually cold temps in the area where we were staying in both AL and NC and even an ice storm in NC.

While the Dawn wouldn't cause any harm, I wouldn't mix it with the anti-freeze just because I am very cautious about anything chemical.

CurveCarver · RV-Dreams Family Member

This is an interesting discussion and great to see so many are willing to help you with your dilemma.

However there is some very basic science that may steer you in another direction.

Pure water will freeze or thaw very slowly @ 32 degrees F. The water in the black tank is in solution that will require a lower temp. The enclosed black water tank will withstand lower temperatures for a longer period of time. Similar to putting a paper bag or plastic over the tomatoes to protect them when the temp drops below freezing. The tomatoes will still freeze but it takes a much longer time b/c the plants are not directly exposed to the cold air. Wind chill does not change the air temperature. Wind chill will cause a surface to be reduced to the air temperature faster because the wind causes the surface to lose heat more rapidly through convection. But it does not make it any colder. In concert with what others have said, the likelihood of the black tank contents freezing @ 31*F in an enclosed environment over a relatively short period of time is extremely low.

The dish detergent simply acts as a surfactant to theoretically reduce the adhesive properties (or surface tension) between liquids or between a liquid and solid surface and is unnecessary and unrelated to this situation.

When in very cold weather as Mike and others have offered, if you want to prevent freezing poor a cup or so of the cheapest windshield washer fluid into the tank, or put a light bulb near to the tank & outlet to add a little warmth.

My guess is that you either have a plug, or as others have suggested there is a mechanical failure that has caused you this problem. I wish you success in finding the intervention that will quickly resolve this inconvenience for you.

HabDaddy · RV-Dreams Family Member

I have to agree with the last comment. In order to freeze the tank solid, you would need to have sustained cold weather for quite some time. Also, if it does get frozen, it is most likely the drain pipe and not the tank.

It sounds to me like you have a mechanical failure with the valve itself. I wonder if the valve broke near the top of the valve allowing you to push/pull the knob but only opens a very small space at the top to allow some liquid to drain out.

NorCal Dan · RV-Dreams Family Member

I had a toilet paper clog my black tank drain and the symptom was as you describe, open the valve and got just a trickle of fluid. I now carry a closet auger in the coach in case it ever happens again. They are not expensive and most hardware stores have them. They come in different lengths so if you decide to get one make sure it will reach your black tank from the drain valve. Here's a link to see what I'm talking about:

http://www.homedepot.com/p/RIDGID-3-ft-Toilet-Auger-59787/100061898