Monday, January 31, 2011

Water Filters

RV water filters and purifiers are something that you should definitely consider before heading off to explore the great outdoors in your RV. A lot of people like to use their own RV water filtration systems even if the campsites they stay at have faucets and water supplies available.

Faucets at campsites usually run to an underground reservoir but the water might not be completely safe. Drinking untreated water means that you risk viruses like Hepatitis A, bacteria like E coli and more.

Some water purifiers use chemicals like chlorine or iodine but most work mechanically. A purifier uses different filtration technologies to make drinking water safe. A purifier is usually better than a filter because it can reduce chemical contaminants, tastes and odors, particulates, sediment, bacteria, viruses and more.

Drinking water filters have been standard equipment on many new motorhomes for years. Even if your RV didn’t come with one, it can be added very simply. The usual location is a small additional faucet placed alongside the kitchen sink. With plenty of space in the cabinet under the sink, changing filter elements is quick and simple.

Another option is an external water filter system. Designed to be used in-line with the water hose that is supplying city water to your recreational vehicle, these in-line filters will treat all the water coming into your RV. In-line filters come in two styles: a simple filter that screws into your hose system and a canister system.

If you want better flow, longer life, and the most versatility in customizing your system, you can install a standard-size canister system. Systems can be configured with a single canister, two canisters in series, or even three canisters for specialty purposes. Since the canisters are a standard size, there is a wide variety of filter cartridges available for them. If you go with a dual-canister system, each canister can contain a cartridge dedicated to a specific task. The first canister should contain a sediment cartridge and the second canister a carbon cartridge. A good combination for most people is a 1-micron disposable sediment cartridge (RV-SED1) paired with a solid-block carbon taste/odor cartridge (CBC-10).

If you want to add an additional function to your system, this is best accomplished by adding a third canister. The first two would contain the same cartridges as a dual-canister system, and the third canister would house the specialty cartridge, such as a Birm or phosphate cartridge. If sediment problems are extreme, triple-canister systems could utilize two sediment cartridges, for example a 5 micron first, followed by a 1 micron and finally a carbon cartridge.

Water filters will remove sediment, and in most cases, improve the taste of the water in your RV. It is unlikely that these filters will do much to improve hard water. To improve hard water you need to use a water softener. Here again, they are installed inline with your incoming water supply. A simple garden hose fitting makes this a matter of a minute or so while you're setting up camp, though a more costly option at about $250. Take a serious look at the benefits.

Filter Methods
- Activated carbon infused with silver - They release metal ions into the water to stop bacteria growing inside.
- Reverse osmosis - water is forced against a semi-permeable cellulose acetate membrane by the water pressure. This separates the water from any contaminants because the water goes through the membrane. Bacteria can build up on the membrane causing a blocked flow so RV reverse osmosis is not recommended for severely contaminated water. A reverse osmosis unit small enough to fit in an RV will only produce a couple of gallons in twelve hours and you cannot use the unit while driving. You will need an additional storage medium. If you are thinking about an RV reverse osmosis unit, check that it is registered as a purifier as well as a filter. RO water filtration does remove large molecules, dirt, sediment and other contaminants. Some RO systems for RV water filtration come with carbon filters, meaning that even more dirty particles can be removed from the water supply.
- Ultraviolet light - These water filtration systems use ultraviolet light to kill bacteria. An UV lamp is effective on microbes but does not remove sediment or dirt. Also, any dirt or sediment can pass into the UV chamber and hide the bacteria from the light, so you will need to use a good filter for taste and odor reduction as well as reducing chlorine, dirt and sediment before using a UV filter. UV filters do need electrical power but they are cheap enough to run.

- Sediment filters are a LOT cheaper at Home Depot or Lowes than Camping World.
- The Seagull IV filter sits under the sink in the back corner. It takes up a little room but is well worth it! All the hardware needed to install it comes with the filter. If you don't want a mounted filter they also carry portable units at General Ecology. Prices start at $533 list and range up to just over $1000.
- Looking for a filter with a counter-top faucet that has similar filtering characteristics to the Seagull IV, at a lower price? A few possibilities are:
-- Flow-PUR Interior Filter from Camping World for $110.
-- Omnipure Q-Series and 3M RV/Marine filter systems start at $100.
-- PurestOne is available for $250.
-- Multi-Pure markets several systems starting at $400.

Installing an under-counter filter
- Here is a great tutorial on how to install an under-counter filter with a sink-top dispenser.
- You don't need to drill through the counter top next to the sink to install a drinking water faucet. The pullout faucet LD uses only uses the large center hole of the sink. They use the base plate faucet mfgs supply to cover the other 2 side holes. If you remove the faucet and the base plate you'll see the other two 1" holes in the sink but the counter under them will not be drilled through. You can drill them through with a hole saw or drill bit without the possibility of the fiberglass counter chipping or cracking and then install a soap dispenser and your drinking water faucet in them and reinstall the pull-out without the base plate using just the single hole mounting method. This makes a much more professional looking setup that will look as if it came that way from the factory instead of being an aftermarket add-on. The hole for the filter faucet needs to be 3/4" minimum but you can use a 1" hole.
Contributors: Mike O, Larry Wade, Malcolm, WxToad
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