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Wouldn’t it be nice if you could buy a shiny, new whole house water filtration system and forget about it for the next decade? Keeping even the best whole house water filter running smoothly requires a bit more finesse than that, but maintenance for most systems is simple. It comes down to replacing the filter cartridges which doesn’t take much time. It’s important to maintain a regular service schedule, however, or your innocent water filter will suffer the consequences…
How to Change a Whole House Water Filter
Guess what? With the right tools, you can replace a whole house water filter cartridge in minutes. It’s really that easy when you know what you’re doing and have the right supplies.
Before you begin, set aside the following materials:
- A bucket
- An extra bucket with warm, soapy water (extra)
- Bleach to sanitize filter housings (extra)
- Housing wrench
- New filter cartridges
From there, replacing a whole house water filter is pretty straightforward. For a visual of the processes, this video can help!
- First things first: turn off the main water supply. All you need to do is shut off the valve attached to your main water line, or the inlet valve located before the filter if you have one. Some models include a built-in valve for even easier filter changes, so check the instruction manual to be sure!
- Open up all the nearby faucets to allow any water remaining in the pipes to drain out. A good sign that you’ve drained enough water is when pressure and flow drop to a trickle. The reason for this is simple. If you don’t drain the water, you may end up with a big, watery mess on your hands!
- Have an outlet valve, too? Close it to prevent any remaining water from flowing back into the whole house filter.
- Each water filter housing should come with a pressure relief button. Hold this down for a few seconds to release any built-up pressure.
- Get your bucket ready! Unscrew the housing with a wrench, using your trusty bucket to collect the water that will flow out.
- Take the old filter cartridge out and set it aside for proper disposal.
- This step isn’t strictly necessary, but to keep the housing extra clean it’s wise to wash it out with soapy water or diluted bleach. If you do decide to clean the housings, always rinse them well with clean water when you’re done.
- Check the O-ring on the housing to be sure it’s in good condition. If not, replace it. If it is, just lubricate it with food-grade silicone grease, available at most hardware stores. Also, make sure it’s properly seated.
- Put the new water filter cartridge inside the housing and screw the housing back on. In most cases, you should be able to tighten it well enough by hand. If the components are made of plastic, avoid over tightening to avoid cracks.
- Rinse and repeat steps 4 to 9 for each housing and filter cartridge of your whole house water system.
- Gradually turn the water back on, opening all valves installed before the system.
- Observe everything carefully, especially in the areas you just worked on. If any leaks are present, shut off the water and tighten fittings where needed.
- Once all leaks are gone, open the water supply again, along with all the valves downstream of the whole house water filter.
- To flush out the filter and remove any air bubbles, run several taps for a few minutes. If you’re not sure how long is enough, check the instruction manual. A good sign that the flush is complete is when all sputtering has ceased and the water pressure and flow rate have returned to their usual state. Just shut off the taps, and your water filtration system is good to go.
- After you’ve cleaned up, mark your calendar so you remember the last filter replacement so you can better estimate when your whole house water filter needs servicing again.
Well Water? No Problem!
The maintenance process is exactly the same whether you’re on city water or well water, so this guide works well for anyone!
What to Do If the Housing Gets Stuck?
The first thing to check if you can’t unscrew a water filter housing is whether or not you’ve released enough pressure. Try opening the faucets again, and hold the pressure release button down a little longer. No luck? Here’s a few troubleshooting ideas.
- Firmly tap on the housing head outside the stuck thread to help loosen it.
- Blow hot air from a hair dryer across it, or hold a wash cloth soaked in hot water over it for a similar effect.
- If all else fails, you can get more aggressive with the unit once you’ve removed it fully from the waterline. You can place it in a vice and force the housing open. Use a metal wrench instead of plastic so you can apply more force without the wrench bending. Or use 2 plastic wrenches one on top of the other. A tube can provide additional leverage. Just be sure that you turn the wrench clockwise with slow, firm pressure.
What can you do to stop this from happening every time you want to replace a cartridge of your whole house water filter? For one, make sure that the O-ring is clean and in good shape (replace if needed). Then, lubricate the O-ring with silicone. Also, make sure that both seat and contact surface inside the head are nice and clean.
Filter Cartridge Replacement Frequency
As common sense would tell you, how often a water filter cartridge needs to be replaced depends on how heavily it’s used. The factors involved include:
- The size, type, and filtration capacity of the cartridge. Cartridges are all different, and some last longer than others. Check the capacity of your water filter to find out how many gallons it can process before replacement is required.
- Your water usage. If you have a large family with an affinity for long showers, expect to change the filter more frequently than if you use water sparingly.
- Water quality. If the water feeding your filter is well water, high in sediment, extremely hard, or otherwise difficult to process, it will lower the lifespan of each cartridge.
For a ballpark figure, the average water filter lasts a maximum of six months. Sediment pre-filters need replacement more often, usually every three months depending on water quality. Standard charcoal water filters boast a somewhat longer lifespan, and post-filters last the longest – sometimes up to a year!
Keeping on a regular replacement schedule is always wise, but if you forget, you’ll notice warning signs begin to crop up. Water discoloration or worsened taste is a common indicator that a filter change is due. The water flow rate may also slow, as an overworked filter cartridge can easily become blocked. When you do change the water filter, you can tell from the state of the old cartridge whether or not you should replace it sooner next time. If it’s clean as a whistle, try waiting a few weeks longer. If it’s heavily clogged, check it a few weeks earlier.
Forgot to Replace? The Risk of Neglecting Your Whole House Water Filter
Forgetfulness happens. If life gets busy and your water filter maintenance schedule falls by the wayside, what will happen? At first, it just becomes less effective. More harmful particulates make it through the system, and your water pressure might drop. The longer you wait, the worse it gets. More and more junk will end up in your drinking water, and your appliances will lose the protection the water filter once provided. Go more than a year, and you’re putting your health at serious risk. Bacteria and mold can build up inside the cartridge and even infest the entire system, eventually making it into your drinking water. No, thanks!
In such a case you might want to consider installing a completely new whole house water filter.
The Short of It
Once you get the hang of it, maintaining your whole house water filter only takes a few minutes of your time every few months. It’s a slight hassle, but it’s worth the effort to protect your home’s plumbing system and provide your house with water that’s safe and delicious.