Guides · RV
RV Drinking Water Filter Basics
City-water hookups, onboard tanks and taste carbon — what to filter where, and the maintenance that keeps an RV system honest.
Three water paths in an RV
City-water hookup: campground water enters through a hose and goes straight to the fixtures. This is the simplest and most predictable path.
Onboard tank: water you filled somewhere else, stored in a tank that may sit for weeks. Tank water needs attention to hygiene as much as to filtration.
Drinking-water tap at the kitchen sink versus the rest of the coach: most owners filter only the drinking point and leave showers and toilets unfiltered.
Filtering the hookup
An inline hose filter before the coach protects the whole plumbing from sediment and reduces chlorine taste. It is cheap, replaceable, and the first thing to add.
A dedicated drinking-water cartridge at the kitchen tap adds a finer carbon stage for taste and, if you want it, a health-based claim for lead or cysts.
Do not rely on a single taste cartridge for microbiological safety. Campground water is usually treated municipal water, but not always.
Tank hygiene comes first
Sanitise the fresh-water tank at the start of the season and after long storage, following the manufacturer's procedure. Filtration downstream of a dirty tank is a losing battle.
Drain and refill when the coach sits. Stagnant water in a warm tank is the most common source of odd taste and odour complaints.
Use a dedicated white hose for drinking water and store it capped and drained.
Winter, storage and cartridges
Freezing splits filter housings and ruins hollow-fibre cartridges. Drain housings and remove cartridges before a hard freeze; many owners keep a bypass plate for winterising.
Replace cartridges at the start of the season rather than mid-trip. A year-old cartridge has been through temperature swings even if it saw little water.
Label the installation date on the housing. RV cartridges are notorious for being forgotten until the water tastes wrong.
A practical setup
Hose filter on the inlet, a two-stage under-sink unit with a carbon block at the drinking tap, and a spare cartridge in the storage bay.
If you travel where water quality is uncertain, carry bottled water for drinking and keep the filter for washing and taste.
Test the drinking water once a season if you use a lot of non-municipal sources — a cheap bacteria test is worth the peace of mind.
FAQ
Quick answers
+Is a hose filter enough for drinking water?
For taste and sediment, often yes. For health-based claims such as lead or cyst reduction, add a drinking-water cartridge with that specific certification at the tap.
+How often should RV filters be replaced?
Follow the rated volume, and replace at the start of each season regardless — storage temperature swings degrade cartridges even when they are not used.
+Can I drink water from the onboard tank?
Yes, if the tank has been sanitised and the water source was potable. Filter at the tap for taste, and treat the tank as a hygiene system rather than a treatment system.