Frozen Water Tank and pipes

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New member
Jan 2, 2013
Hi all,

I have an embarrassing situation and need some help. I live in CT and have a 1993 Winnebago Itasca 32' Class A. I left on vacation last week and forgot to drain my fresh water tank. It is about half full and I also did not purge the lines. I came home and sure enough it is frozen solid (and 9 degrees expected for the next two nights). I saw that the water filter under the kitchen sink is almost horizontal now when it was vertical before so obviously something has already given way. How do I thaw everything now that it is below freezing and looks to stay that way for at least the next week or so? Should I look for a place to put it inside and let it thaw (i.e. an RV service center that will probably charge me storage) or is the damage done and I just wait it out and see what happened when it finally thaws? How screwed am I?
i would think you would be better off to get into a heated building if you can, sooner the better. even if you put heat under it it wont get all the interior pipes. if that is not possible  you could possibly skirt in the sides with tarps or something and put some heaters under it. turn the heat on inside the mh to thaw the inside lines. put a pail under the filter to catch the water as it thaws. ice expands as it thaws so it might be a good idea to open all the taps to allow for some expansion. i also think it might be a good idea to pull the plug out of the hot water tank. i know i forgot to drain the hot water tank on my first tt and it split it wide open. hopefully it wont damage your pump either. i think the lines if they are plastic will take a bit of flex before they get damaged. one time i forgot to put winter windshield fluid in my truck and it froze the windshield washer tank and lines . my neighbour suggested putting icypropyl alcohol in the reservoir. it worked its way through the lines and thawed it out like a charm. any one else ever try this for frozen lines in a mh. sorry to hear about your problems. hope this helps
If the tank is already cracked and would need replacing I think I would consider cutting the top off and removing the ice in chunks. If you thaw it and it is cracked you will have a flooded interior. This assumes the tank is inside and you can gain access to it.
The tank is not yet cracked. It is hard plastic so I don't think it will. I am more worried about the pipes, water heater, water pump etc.
It sounds like whatever damage the plumbing will sustain has already happened - the main water tank has the largest mass, so it'll freeze solid last.  The best thing you can do is prepare for the thaw.

While everything's frozen solid, I'd remove or if necessary cut the line going from the fresh water tank to the pump and plug the tank end.  Or extend it with plastic tubing until the open end is above the level of the water in the tank.  Get some tubing that fits snugly over the end of the frozen line and secure it with a hose clamp.  Make sure the line is intact between there and the tank and the water should stay in the tank as it thaws out.  If you open the tank drain you'll have a fighting chance of it draining outside the rig as it thaws.

Remove the drain plug from the hot water tank and see if it drains.  If it's frozen solid, your best bet would be to remove it from the rig before it thaws, to keep 6 gallons of water from flooding the interior in case it's split wide open.

Or see if there's a way to rig a drain pan underneath the water heater, with a drain line going to a large container to keep the flood damage to a minimum.  Maybe wedge a plastic tarp under the heater to contain and direct any leakage towards your container?

Then all you'll have to deal with is the small quantity of water inside the pipes and in the water filter.  That's much easier to clean up compared to everything that would leak out of the tank.
Inclined,  Is your water tank inside or outside your living space?  Is it possible to determine if the tank is broken?  I sometimes get freezing near the outlet of my water tank.  This is usually solved by pouring about five gallons of HOT water in the tank filler to get the pump moving water again.  Some source of external heat around the tank outlet, judiciously applied so as not to melt plastic, should help.  Once flow is established keep adding hot water to melt the remaining ice.  If your tank is not damaged you should be able to get some flow with some tubing connected to the tank outlet and set up to drain into a bucket or onto the ground depending on how much skating rink you wish to create.  If by the way this ultimately resulted in someone making it in the NHL............... GB, by the way, is not my favorite person but we do love our hockey up here.

The broken parts such as your filter will leak water when thawed.  A bucket or two might be useful here.  My Hot water heater drains to the outside.  It has a pan under the tank which, I think, would direct water from a broken tank outside.  Personally, if mine was frozen, I would fire it up for a short time and see if water (used to be ice) either stayed in the HWH or ran outside via the pan.  Ice, by the way, does not expand as it thaws.  Freezing of water to ice results in expansion.  This is why freezing breaks things.  Not all liquids do this.

Lou Schneider said:
It sounds like whatever damage the plumbing will sustain has already happened - the main water tank has the largest mass, so it'll freeze solid last.  The best thing you can do is prepare for the thaw.

Just a thought.  It sounds like the OP definitely needs to get the Winnie thawed out.  Do you think it might be better to thaw it out while keeping a close eye on it and maybe repairing/patching/shutting off as the thawing takes place?  I am thinking the FWT should be ok with all that room for expansion.  The water heater, if full, could be a problem.  The pump, head, and the rest of the system will be hit and miss.  But if allowed to thaw at some kind of a controlled rate, it might give the OP some time to keep any damage to a minimum without allowing more damage to occur.
One area of concern that has not been mentioned yet is the waste piping. All the sinks and shower(s) have a trap that is filled with water, as in household plumbing, this is to prevent sewer gases from entering the living space. Sinks are typically accessable from the under countertop space. Shower traps though, are often inaccessible. I was going to suggest heating a 1/2 gallon of RV anti-freeze in a pot and then pour it in the shower drain, thinking that it would thaw the frozen plug of water and then displace it leaving the trap fillled with anti-freeze. BUT, if the trap is already cracked it could just make more of a mess. No other thoughts right now, but if I come up with any I'll be back. Best of luck.
The night that I posted this I put the heat on in the RV all night and covered the water tank with an electric blanket. It was all thawed out by mid-day the following day and I was able to drain it all. It looks like the only damage was the busted water filter under the kitchen sink. She's all empty and  winterized now. Had an angel on my shoulder for this one. Thanks for all of the help and suggestions.
Keep a close eye on it when you dewinterize it and put it under pressure.  You may have some cracked fixtures or connectors hiding in there just waiting to surprize you.

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