Monday, November 28, 2022


Quick RV Tech Tip: There’s still some water in the fresh water tank when I winterize. Is that okay?


Dear Dave, 
I *thought* I fully drained my fresh water tank when winterizing. However, I realized the drain valve comes off the side of the tank and leaves about 1.5 inches of water in the bottom. Even tilting the trailer as far as possible still leaves about 1/2 to 3/4 inch of water in the tank. Is this amount of water safe to allow it to freeze? I thoroughly blow out the rest of the system and run the pump dry, and would prefer to only use RV antifreeze in the waste traps. —Jim, 2022 Gulf Stream 189DD travel trailer

Dear Jim,
This is common not only with the fresh water tank but also with the water heater. The drain plug is about 1.5″ above the bottom of the tank so you will have water sitting there as well. Since most tanks need to sit on a flat floor or surface, the design does not allow a drain valve to be flush with the bottom or come from underneath. The small amount of water sitting in the bottom of these tanks is not an issue when it comes to freezing as there is sufficient room for the water to freeze and expand without doing damage.

The main concern is water sitting in the pipes, faucets, ice maker, toilet valves and other smaller components that do not have the space for expansion when the water freezes. Since you blow those out, you are doing the right thing. The antifreeze in the “P” traps is good, as well.



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Jesse Crouse
5 days ago

From a Plumber. The reason Plumbers use that description is because the vast majority of our customers use it. The correct professional term is WATER HEATER.

21 days ago

What your opinion on Flex amor,, instead of chalking the roofing RV .. mostly on class C and class A

Dan Kruger
21 days ago

I commented on the subject about Enable us to be Honest a few issues ago and got accused of maybe being a little drunk or weird….I still stand by what I said u want money from us to keep u honest….see my point…. u word it wrong…..if the same people want to say the same things put your last name up in your comments then….I do….but I still enjoy the issues…

21 days ago
Reply to  Dan Kruger


21 days ago
Reply to  Dan Kruger

Maybe you are a little drunk… did not follow anything you said.

Dan Kruger
21 days ago
Reply to  Cee

again…only first names…really….in order for them to not be bias for paid ads they ( chuck woodburry ) want money from us…if u cannot understand this comment you must not understand much of anything. I’ve said my peace and will move on….

20 days ago
Reply to  Dan Kruger

Happy Trails

Thomas D
21 days ago

Old plumber joke ( or saying) Hot water heater!
Why do you want to heat HOT WATER.

Bob M
21 days ago

I thought I drained my water tank completely. Then I pulled it up my driveway and onto the road which had a slight slope. I was surprised with the amount of water coming out. My hot water heaters owners manual say don’t worry about the water that don’t drain out of the tank when winterizing.

21 days ago
Reply to  Bob M

When you drain the hot water heater (HWH) empty, that’s also a good time to use one of those long, slender, hook-nosed, high pressure sprayer heads to break up and flush out the calcium deposits that build up over time inside the HWH tank. I took 3 – 4 hours to do mine the first time and was surprised at the amount I flushed. I do it every time I winterize now.

21 days ago
Reply to  Ray

Why are you guys heating hot water? :<)

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