Can I Leave My RV's Holding Tanks Full During The Winter?

by Scott
(Bow NH)

I just got a used Class A Motorhome and the black water and gray water tanks are full and it is going to snow. I found that I have no hose to drain the tanks. Will it damage the tanks to leave them full over the winter? If so is there anything I can do to prevent damage to the tanks if I can't get them drained.

I've never had an RV so any help you can give me will be greatly appreciated.

ANSWER: Hi Scott thanks for submitting your question on our Ask An RV Question Page.

Considering where you live, I would not recommend leaving any liquid in any of your holding tanks. The chances are good that they could freeze and expand and damage your holding tanks.

RV Sewer Hoses are inexpensive and I am sure that you can find a convenient dump station in your area, so I would suggest that you dump your black and grey water holding tanks as soon as possible.

Since you are new to RVing I also suggest that you read the article Winterizing Your Motorhome so you can take all the steps needed to properly winterize your RV.

Hope this helps.

Over 1,500,000 successful roadside rescues. Good Sam Roadside Assistance.

Happy RVing

RVing Al

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Comments for Can I Leave My RV's Holding Tanks Full During The Winter?

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Absolutely not........
by: Anonymous

Unless you keep it heated above freezing as was suggested you will have a repair bill and a mess bad enough to make you quit RV I got forever.

We were all newbies once
by: Cochise49

In our first self-contained rig,35 years ago, I was taking a shower and the water rose up to my ankles. Thought there was a clog and got upset with the DW and DS about putting the wrong paper products in the tank. Turned out the gray tank was just full. Rif was a dealer repo and tanks were not empty. Was rewarded with learning to dump after a call to my dad who was a seasoned RVer. Many such learning opportunities came with each rig (5) since then. Find a dump station if you can. A local septic tabk company may be able to help or your local waster treatment plant run by the water utility. Failing those, follow the RV antifreeze sugestion and hope for the best. If you have a new enough unit, the heating ducts may pass adjacent to the tanks and provide some protection at the price and inconvenience of propane refills. Get the tanks empty even if you have to make a trip to a campground that is open all year. Good luck!

6 month old feces?
by: Bobby Frozen Poo

the anti freeze is a great idea. dump 3 gallons in each for good luck. The thing that puzzles me is as a newbie to RVing I can honestly say I knew saving fecal matter in my Black tank for 6 month is nothing short of disgusting. The RV police are coming to confiscate your motor home.Please clean out your belongings

by: RV Sellor Ret'd

RISKY BUSINESS. While the natural decomposition of human waste is ongoing even in cold weather the net effect is minimal with regard to lowering the freeze point of waste product. If you can picture 45 gallons of human waste in your driveway along with pieces of high density polyethelyne ( tank pieces) one begins to see the big picture. Clean-up is stomach retching and probably enough to make you want to dispose of the RV. If the tank is full you do not have enough room for the quantity of anti-freeze necessary to provide adequate protection.

I personally experienced a sewer tank freeze up in my brand new rv a number of years ago and I promise you , you'll be sorry you didn't go buy a sewer hose and dump your tanks. Also it will pay you to winterize the coach as much as a pain it may be frozen water tubes,water pump, toilet valve etc can get expensive and time consuming to repair. I have on the other hand been lucky by placing a 110v milk-house portable heater in my coach and set the thermostat @ 60degrees opened the kitchen & bathroom cabinet doors and made it thru a couple of pretty cold winters here in NJ Good Luck.........

by: Anonymous

Dump a jug of RV Anti-freeze into each tank.

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