Dear Dave,
I just got a new trailer (love it) and purchased a Waterdrop RV Inline Hose Water Filter to put on the supply hose. Now that I am done with my first trip, how do I treat the filter? It retains water and I don’t want it to leak or evaporate while stored inside the trailer. Also, could that water become moldy inside the filter? It could be another month before I’m on the road again. —Kevin, 2022 Jayco 199MBS
Dear Kevin,
Your Waterdrop inline water filter is very similar to the Shurflo and Omni we have used for years. We have just taken the filter off the hose when done camping, set it in a pail to let it drain, and then let it dry.
Disinfecting the water filter
If you want to take it a step further, I would recommend putting a few tablespoons of bleach into 1/2 gallon of water and pouring it into the water filter when it’s in the pail. That should thoroughly disinfect the filter. Mold spores can sit dormant in water and places, so this would ensure they were taken care of.
We went away from the inline filter a few years ago as it would get plugged due to the hard water in the Midwest rural areas. Instead, we went to the residential Omni filters with a cartridge.
This is a smaller under-the-sink version for smaller trailers, and you can get larger ones for the big rigs. What I like about these is I can just change the cartridge for about $2 at a home improvement store vs. replacing the entire inline version.
This way we can get a filter that not only filters calcium, lime, and sediment, but also has a taste filter. You could use this and throw the filter away when you are done camping, and install a very inexpensive one the next time you go out. This way you would be assured it was clean and disinfected.
Dave Solberg 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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Sorry Dave but I question the advice to put bleach into the water filter, I believe that, that is totally unrecommended
If a cartridge filter is ONLY a particulate filter, it is likely spun polypropylene, and will likely not dry out EVER because it is too tightly wound to allow the water to drain (capillary attraction is strong) or air circulation. Pleated paper filters MAY dry out but would need a very low humidity environment in which to do so. IF the cartridge contains activated carbon, putting bleach into the filter will destroy the carbon. The purpose of activated carbon in a filter is to remove organic, dissolved contaminants by binding them to the dangling bonds which is what chlorine bleach is.
I just did a quick check looking for the $2 filter cartridge refills you mention. EVERYTHING I can see is more like $20. Was there a typo or, is google missing something?
I replace my cartridge filter if it’s going to be more than a month before the next trip. I suspect the filter will still be moist even though most of the water has drained away.
I like the cartridge over the hose filter for the long term expense incurred and length of service between changes. Please realize that the housing can become contaminated if it just sits there, holding a contaminated filter in water not being circulated. Just like the rest of the plumbing, a good periodic washing with that chlorine solution of the inside surfaces of the cartridge filter container wouldn’t hurt.
As you said it will drain if it’s left in a vertical position after which it will dry. I’ve been using inline filters since 1978 and haven’t experienced any problems yet, of course there’s always a first time for everything.