Black Tank Valve refuses to open

Deedee

Member
My Black tank valve refuses to open, it has been cold here the past few days, dipping down to -7C at night with highs of -3C in the day, but I would be really surprised if it froze.
It never has before. I have pulled on it and pulled on it and it won't budge. I really need to empty my tank. Does anyone have any suggestions?
Thanks
D
 

PUG

Pug
Could be froze if it had been working fine before the cold snap.
try a little heat being careful not to get anything to hot and burn your hacienda down.
 

lwmcguir

Well-known member
Add a little Dawn or any other concentrated surfactant each time you dump. (starting a new tank full) The surfactant will actually help let the valves slide all the time and helps even more when it is cold. Only works down so low and then you are going to freeze up anyway unless you heat trace the valve area.
 

danemayer

Well-known member
I had my Landmark in Colorado mountains at -20 and -30 last month, which caused the tank valves to freeze a couple of times. They thewed by themselves on warmer days - above 20 degrees. But I was also running the furnace at 72-74 to get a lot of heat into the basement. And my Landmark might have more insulation than the Sundance.

At one point, I had to thaw out the Gray #1 valve with a hairdryer. Had to take out a couple of underbelly mounting screws and peel back the corner of the underbelly near where the gray 1 1/2" drainpipes exit the underbelly. Fortunately, that's where the Gray #1 valve was located. I didn't see the Gray #2 or Black valves, but probably could have found them by taking out more mounting screws.

So I'd suggest running your furnace to try to get the basement warmer. If that doesn't do it, and if it's not going to warm up during the day, you'll probably have to get under the rig with a ratchet and look around for the valves, backtracking from where the 3" pipe exits the underbelly.
 

westxsrt10

Perfict Senior Member
My Black tank valve refuses to open, it has been cold here the past few days, dipping down to -7C at night with highs of -3C in the day, but I would be really surprised if it froze.
It never has before. I have pulled on it and pulled on it and it won't budge. I really need to empty my tank. Does anyone have any suggestions?
Thanks
D
Is the valve on the exterior of the RV? (like mine) If so pour a few gallons of warm water over the valve.
 

danemayer

Well-known member
If you get underneath the rig to work on it, get jacks or something to make sure a landing gear failure doesn't drop the rig on top of you.
 

Deedee

Member
Is the valve on the exterior of the RV? (like mine) If so pour a few gallons of warm water over the valve.

I am beginning to think my valve is not frozen, but stuck, as I put a hair dryer on it for 45 minutes and I also poured hot water on it. I have no idea how to get it unstuck. I have also discovered my Gray Tank Valve is not shutting properly either. Any suggestions would be most helpful. My valves are in the UDC.
D
 

danemayer

Well-known member
My valves are in the UDC.
I assume you mean the valve handles that you pull are located in the UDC. The handle is attached to a cable. The other end of the dable is attached to the valve. The valve would be located where the drain pipe comes out of the tank. If the valve is frozen, the freeze is likely not at the handle, but at the valve and that's where the heat needs to be applied.
 

Deedee

Member
Thank You..I just wanted to mention I am very new with RV's and I am still learning about everything ...sigh I am not mechanically inclined, but I think I know what part you mean. I will try that tomorrow. But if that does not work, what would be next? I called my dealer but they just think I am a hormonal woman...:) and won't help me. (another story)
 

danemayer

Well-known member
I'm pretty new as well, and have had to deal with more than a few problems. The people on this forum have explained a lot to me and have helped enormously.

My experience with the drain valves is limited to freezing and thawing. But if yours is not frozen due to low temps, my guess would be that it's mechanically stuck. In either case, I'm pretty sure you have to gain access to the actual valve mechanism to work on it, which on my unit means dropping part or all of the underbelly (the cardboard-like sheet that's underneath the unit). That's the only way I know to gain access to the valves on my unit.

When we were in Colorado for 5 weeks, the nearest dealer was 2 hours away with a tough drive thru a mountain pass - with snow on the roads most days. Getting a mobile repair guy in would have been pretty pricey because I'd have to pay for their travel time. All that to say that I was willing to get pretty adventurous in fixing things because I really didn't have any other good choices.

Anyway, if you can follow the large drain pipe back to where it joins the tank, 10 or 15 minutes with a hair dryer will probably get it working. If that doesn't free it up, and you can get to the valve, you might be able to open it with a pair of pliers.

If it's not working, but you can get it open, for a temporary workaround, you might be able to use one of these
http://www.amazon.com/Valterra-T58-...JS/ref=sr_1_13?ie=UTF8&qid=1298773719&sr=8-13

It goes on the end of the drain pipe where you'd normally attach the sewer hose. You'd be able to leave the broken black valve open until you can get it fixed, and not leak sewage in the meantime. If you did use this in cold temps, you'd probably have to put heat tape on the drain pipe to keep the sewage from freezing in the exposed drainpipe area.
 

cookie

Administrator
Staff member
Deedee, you will need to do as others have suggested. To access the valve itself, you will need to drop the black plastic belly material on the off door side near the sewer drain pipe. Follow the big black pipe till you come to the valve. Use your hair drier there. You will need a 3/8 socket or open end/box wrench to remove the screws that hold the belly up.

Peace
Dave
 

Bob&Patty

Founders of SoCal Chapter
DeeDee, at your 1st chance get the Valve that Dan Mayer suggested. Put it on and leave it on. I would however, install it with PVC pipe glue...they can come loose and fall off. Don't ask. They are a life saver. We had the black tank valve stick open on a trip. Then on the way home the OEM sewer cap came loose (blew off) and we left DNA on the road for 500 miles.
 

jheitman

Well-known member
My black tank valve is getting harder and harder to open and close. Is there anything I can do to loosen it up ?
 
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