By Greg Illes
Most – if not all – RVs come with a water filter installed, usually under the sink where it filters all the water running out of the faucet. But that raises the question, why filter perfectly good water? The answer to that question is another question: How good is “perfectly good”?
Many RVers use the water that the RV park supplies, straight from the tap. After all, that water comes from treated sources and should have no problems. Right?
Well – maybe. Yes, it’s reasonable to assume that a typical chlorinated municipal supply is biologically safe. But that’s only guaranteed at the water treatment plant output. The distribution system can be full of flaws that degrade the quality of the water before actual use.
And that’s not to mention if the local water is coming from a private well, with something subtle in the treatment protocol not working properly. UV irradiation bulbs burn out, filters get clogged, etc.
Aside from health issues, rust and sediment are the biggest culprits, and they increase with the age of the distribution system. The photo shows a graphic example: a new ceramic 0.5um (micrometer) filter, and a second one with only a few hundred gallons through it. It was so clogged with rusty sediment that the flow had slowed to a trickle. It had never been used anywhere except from certified sources.
Odors and tastes can be “safe” but still objectionable. A friend’s house, in another town, provided municipal water with a noticeable “stink” when it first came out of the faucet. Nobody got sick, but it wasn’t pleasant.
Bottom Line: When I fill my motorhome’s fresh water tank, I would like to be certain that the next 75 gallons of water I drink, shower with, or use for cooking, is going to be good for my equipment, and good for me.
But such certainty is a real challenge. I can’t possibly test for contaminants and parasites every time I need a fill. And I can’t have every single possible filtration and treatment protocol (there are dozens) applied to all the water I take on.
The answer, as with so many things in life, is a compromise. With properly treated water as a baseline, I have settled for a simple configuration: a fairly fine-pore sediment filter augmented with activated carbon. The fine-pore filter removes all but the tiniest particles of sediment and screens out any nasty protozoans that might have crept in (e.g., giardia, cryptosporidium). The carbon takes out any odors and tastes. For me, this is an acceptable balance between trouble/cost and quality/safety.
In order to keep an eye on my filter’s health, I chose a clear whole-house housing like the Pentek 150071 (shown). The business of actually doing the filtration is handled by a special high-flow cartridge like the Pentek Flo-Plus, which has great flow performance even with fine (0.5um) filtration. I would hate to have great water at the cost of an hour’s wait to fill my tank. (Not to mention holding up the people in line behind me.)
I screwed pipe-to-hose adapters into the housing so that it could be connected right at the source faucet – that way, I don’t let any “strange” water into my hoses or fittings.
YMMV (“Your mileage may vary,” for those who don’t know) – Note that different people (preferences, allergies, etc.), different water, locales, and use demand different solutions. What works for me might not be your best or safest choice. I’ve only outlined my configuration here by way of example, and not as advice. I’ve seen people with dual-filter setups, UV-light setups, silver-impregnated cartridges – the list goes on. Some folks don’t bother with filtration at all. Some people boil every drop that they drink. It’s up to each individual to sort out their own best approach.
Please feel free to leave a Comment about your own “adventures” with water, and your own filter solutions. We can all benefit (and often be entertained) by each others’ experiences.
Happy travels, and safe and healthy living as well.
Greg Illes is a retired systems engineer who loves thinking up RV upgrades and modifications. When he’s not working on his motorhome, he’s traveling in it. You can follow his excellent blog at www.divver-city.com/blog .