An RV water filter sits on the hose between the campground spigot and your RV, and its main job is taste, odor and sediment. What a given filter actually removes is what its maker lists and its certification covers, nothing more.
RV Water Filters Explained: Inline, Canister and Softeners, Micron Ratings and When to Change Them
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At a glance
- What it does: cuts chlorine taste, odor and sediment; it does not make water of unknown quality safe to drink.
- Inline or canister: the lower the micron rating, the finer the filter; inline hose filters are printed down to 20 micron, canister systems reach 0.2 micron, and Clearsource's three-canister system flows less than its two-canister one.
- When to change: makers differ, from 2,000 gallons or one season to 10,000 gallons or one year.
On this page (7)
Our picks
- Camco TastePURE 40043 inline RV water filter: 20 micron KDF and carbon for taste, odor, chlorine and sediment; one season per cartridge
- Camco Evo X2 two-canister RV water filter kit: 5 micron, then 0.5 micron cartridges in two canisters
- Clearsource Premier two-canister RV water filter system: 5 micron sediment first, then 0.2 micron absolute
- On The Go OTG4-StdSoft portable 8,000 grain water softener: only worth it on hard water; regenerates with one 26 oz box of table salt
Is an RV water filter worth it?
For chlorine taste or silty water, yes. Camco rates its TastePURE KDF/carbon filter at 20 micron for taste, odor, chlorine and sediment. Builders treat it as optional; Jayco's 2027 manual says to "consider using an inline water filter".
It will not fix sulfur smell: Clearsource says plainly that its systems do not treat it. If your water smells, start with filling and sanitizing the fresh water tank, not with a cartridge.
Nor does it make water safe. Pentair's OmniFilter RV1 instructions warn against using the filter with water that is microbiologically unsafe or of unknown quality without adequate disinfection.
Inline, canister or under the sink
More stages filter finer, but you give up flow at the faucet. An inline filter is one cartridge between two hoses; a canister system holds one to three cartridges, on a stand at the spigot or built into the RV; an under-sink filter treats one tap.
| Model | Micron rating as printed | Flow as printed |
|---|---|---|
| Camco TastePURE 40043, inline hose | 20 micron | Not printed |
| Camco Hydro Life HL-180, inline hose | Not printed | 2.5 GPM maximum |
| Pentair OmniFilter RV1, inline hose | Not printed | 1 gpm |
| Camco Evo X2, two canisters | 5 micron, then 0.5 micron | Not printed |
| Camco Evo X3, three canisters | 5, then 0.5, then 0.2 micron | Not printed |
| Clearsource Premier, two canisters | 5 micron, then 0.2 micron absolute | 6 to 6.5 GPM at 40 PSI |
| Clearsource Ultra, three canisters | 5.0 micron, 0.5 micron, VirusGuard | About 4.5 GPM at 40 PSI |
| Forest River WaterPur CCI-10CLW12, built in | 15 micron prefilter, 5 micron layer, carbon block | 2.5 GPM |
| Camco Hydro Life HL-170, under counter | Not printed | 1 GPM maximum |
Figures from Camco, Pentair, Clearsource and Forest River; the Clearsource flows are its own test at 40 PSI. Camco marks the Evo X3 for exterior use only.
Tip: Put a sediment stage first. Clearsource notes that a 0.2 micron filter on its own would be prone to clogging unless a sediment filter sits ahead of it.
What the micron and NSF numbers mean
A filter removes only what its ratings cover. Micron is the size of particle the media is rated to stop. On Clearsource's scale, silt and sediment run 50 to 150 microns and bacteria range from 0.2 to 10 microns.
Clearsource says many small blue inline filters are rated at 100 microns or not at all, enough for sediment but not for chemicals, bacteria or cysts.
Look for the word absolute. The Portland Water Bureau recommends a filter with an absolute pore size of 1 micron or smaller against Cryptosporidium and notes that a nominal 1 micron rating may not remove all of it. Absolute, in Clearsource's words, means each pore is the rated size or smaller.
The NSF numbers are standards, not scores. NSF's own listings describe them this way:
- NSF/ANSI 42, aesthetic effects: chlorine, chloramine, taste and odor, nominal particulate.
- NSF/ANSI 53, health effects: certified contaminant by contaminant, such as lead, cysts, turbidity, VOCs and PFAS.
- NSF/ANSI 401, emerging compounds: named compounds such as DEET, ibuprofen and microplastics.
- NSF/ANSI 44: cation exchange water softeners.
Marks differ by product, so read the claim list, not just the mark. Camco prints the 42 and 53 marks for its TastePURE and Evo cartridges. Forest River's WaterPur was tested to 42 for chlorine and 53 for turbidity and cyst reduction, not lead. Portland's example: two filters can both be NSF/ANSI 53 certified while only one of them is certified for lead reduction.
How often to change the filter
Go by the interval printed for your own filter, because the published figures are five times apart.
| What you have | Interval the maker prints |
|---|---|
| Camco TastePURE KDF/carbon inline | An entire season |
| Pentair OmniFilter RV1 inline | About 2,000 gallons or one recreational season |
| Clearsource canister cartridges | 2,000 gallons |
| Forest River WaterPur CCI-10CLW12 | 10,000 gallons or one year |
| Jayco built-in canister | Start of each camping season, or after exposure to contaminated water |
| Keystone, filter added by the owner | Change it when the system is sanitized |
Intervals from Camco, Pentair, Clearsource, Forest River, Jayco and Keystone.
Change it sooner when taste, odor, color or flow changes; Jayco adds that weak flow may simply mean a clogged filter. Flush a new cartridge before you drink from it, since carbon fines come out black: Pentair says five minutes for the RV1, Clearsource 45 to 60 seconds.
Tip: Pull the cartridge out before sanitizing or winterizing. Jayco notes there is no bypass on a canister filter and that RV antifreeze can harm the cartridge; store a spare away from freezing temperatures.
Where the filter goes, and what it does not reach
The filter goes on the hose, and it only cleans water that runs through it. Clearsource's hookup: one hose from the spigot to the filter inlet, a second from the filter outlet to the RV's fresh water connection. Clearsource, Keystone and Jayco all say to use a pressure regulator, but none states whether it belongs before or after the filter. See RV water pressure regulators for pressure limits.
On city water the filter cleans what comes out of your taps, not the tank: Keystone notes that the city water inlet bypasses the tank and feeds the entire system directly.
Do you need a softener too?
Only if your water is hard. On The Go, a softener maker, points out that filters do not remove minerals such as iron, calcium and magnesium. A softener swaps them out through ion exchange resin, which keeps scale off the water heater and spots off the shower. Hardness is measured in grains per gallon: 0 to 3 is soft, 3 to 7 moderately hard, 7 to 11 hard, and above 11 very hard.
Capacity is grains divided by hardness. On The Go's example: its Standard unit's 8,000 grains at 11 GPG is 727 gallons, about 14 days for a couple using 50 gallons a day.
To regenerate the On The Go Standard:
- Turn off the water supply, disconnect both hoses and drain the unit.
- Remove the top cap and add one 26 oz box of table salt, iodized or not.
- Refit the cap and inlet hose, then rinse very slowly, a stream about the thickness of a pencil, for 12 to 15 minutes.
- Open to a full stream for 3 to 4 minutes, then test with a hardness strip. Soft is 0 to 3 GPG, and the water should not taste salty.
Common questions
Are RV water filters worth it?
For taste and sediment, yes; for safety, no. It does nothing for water already in the fresh tank.
How often should you change an RV water filter?
Clearsource scales the job to use: yearly for the occasional camper, twice a year for the frequent weekender, and every two to three months for full timers. Heavier use reaches its 2,000 gallon rating sooner.
Is an RV water softener worth it?
Only where the water is hard, above roughly 7 grains per gallon. In very hard water a small portable unit needs salt every couple of weeks.
Should I filter the water going into the fresh tank?
Only if you fill the tank through the filter, using the gravity fill or a tank fill valve. Jayco says the tank cannot be filled through the city connection unless a utility center valve allows it.