Saturday, December 3, 2022


Ask Dave: How do I prepare a fresh water tank for use?


Answers to questions about RV Repair and Maintenance from RV expert Dave Solberg, author of the “RV Handbook” and the managing editor of the RV Repair Club. This column appears Monday through Saturday in the RV Travel and RV Daily Tips newsletters. (Sign up for an email reminder for each new issue if you do not already receive one.) Today Dave discusses how to prepare a fresh water tank for use.

Dear Dave,
I have a 2018 trailer and would like to use the fresh water holding tank. I have never used it but the previous owner may have. How do I clean or prepare a holding tank for use? —Carol

Dear Carol,
The fresh water tank in your rig is typically made of rotocast plastic. If you have not used it for a while, it would be a good idea to clean and sanitize it.

I prefer to use a bleach solution. I pour a cup of bleach into a gallon of water and dump it into the gravity fill, which would put it in the tank. Then fill the tank with fresh water and let it sit overnight. It would also be a good idea to drive around a little to get it mixed up. Then, after an overnight rest, run the water pump and clean out all the faucets, shower heads inside and out and the toilet.

What about an ice maker?

If you have an ice maker in the refrigerator, there will be a filter location under the sink that either has a filter in it or has been capped off. I would not run the bleach solution through the filter and the ice maker. It would be better to run a couple cycles of the ice cubes and it should be good. The bleach smell/taste will dissipate in a day or two.

If you do not want to use bleach, Thetford makes a fresh water tank cleaner and sanitizer that you can use instead.

Read more from Dave here

Dave Solberg worked at Winnebago for 15 years developing the dealer training program, as marketing manager, and conducting shows. As the owner of Passport Media Creations, Dave has developed several RV dealer training programs, the RV Safety Training program for The Recreation Vehicle Safety and Education Foundation, and the accredited RV Driving Safety program being conducted at rallies and shows around the country. Dave is a leading expert in the RV industry and author of the “RV Handbook” as well as the Managing Editor of the RV Repair Club.


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James Starling
1 year ago

I think you should run the bleach solution thru all faucets and hot water tank till you smell the bleach. Then top off water tank before letting solution set 4 hours to overnight.

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