12 Reasons Why Your PUR Water Filter Is Leaking – And How To Fix It


PUR water filters may leak because of incorrect installation, a filter that’s too loose or tight, hot water damage, debris, or an incompatible adapter. An ill-fitting O-ring, loose valve, incorrect pouring method, or damaged filter can also cause leaks.  

PUR faucet filters and filter pitchers are known to filter more than 70 contaminants, including lead and mercury. However, they may leak under a few circumstances.

In this article, I take you through the 12 most common reasons why your PUR filter could be leaking and give you some easy fixes. Don’t worry, this guide covers both faucet filters and filter pitchers.

Types of PUR Water Filters

Here’s a quick look at the different models of PUR faucet filters and filter pitchers. This article is aimed at users of the following filters.

Faucet Filters:

  • PUR Basic Faucet Filtration System
  • PUR Classic Faucet Filtration System
  • PUR Advanced Faucet Filtration System with MineralClear filter
  • PUR Bluetooth Ultimate Faucet Filtration System

Filter Pitchers:

  • PUR Basic 7-Cup Pitcher
  • PUR Classic 11-Cup Pitcher with LED
  • PUR Classic 18-Cup Dispenser

12 Reasons Why Your PUR Water Filter Is Leaking

1. Incorrect Installation

The most common reason for a water leak is incorrect installation. Follow the directions for your specific filter to make sure there are no leaks. Here’s a rundown on how to correctly install a PUR faucet filter and PUR filter pitcher.

For a PUR faucet filter:

  • Remove the aerator and washer from your tap. You can use a rubber jar opener in case the aerator does not come off easily.
  • Find the adapter from the PUR package that fits your tap (keep reading for more information on adapters).
  • Tighten your adapter and fix the washer.
  • Twist the back cover off the device and fit the filter inside. Make sure that the filter is centered and the O-ring is intact. The filter will fit loosely.
  • Replace the back cover.
  • Depending on the model of your faucet filter, you may be able to fit the device on the tap with one click.
  • If your filter does not support one-click installation, fasten the device on the tap by keeping it level.
  • Position the filter in a level way, make sure that the PUR logo is facing you, and tighten the mounting nut, turning it counter clockwise.
  • You will hear a ‘click’ sound when the device is installed.

For a filter pitcher:

  • Soak the filter in water for 15 minutes.
  • Wash the pitcher and dispenser and rinse it with soapy water.
  • Hold the filter under cold running tap water for 15 seconds.
  • Insert the filter into the pour tray and pull the filter down. Twist it clockwise to create a snug seal. You will hear a click sound as the filter locks in place.

If your PUR filter is also producing black water then read this article here.

2. Filter Not Tight Enough

If your PUR faucet filter has not been wound tightly enough that it ‘clicks’ into place, the water may leak around the filter. It must snap into place for optimal filtration.

In your PUR filter pitcher, unfiltered water may leak into the filtered water reservoir if the filter is not tight enough.

To rectify this, remove the filter and reinstall it. Wind it counter clockwise just until you hear the click sound.  

Also, make sure that the filter cap of your device has snapped into place.

3. How Water Damage

Thermal damage can cause your filter to leak or allow unfiltered water to pass through. This is because the temperature of the water affects the filtering agent and filter weave inside the cartridge. In fact, thermally activated contaminants like chlorine may be released in the process.

PUR recommends never running hot water through your filter.

For PUR faucet filters – Do not use the water above 100˚F (38˚C).

For PUR filter pitchers – Do not use with water above 82°F (28°C).

4. Debris In The Filter Housing Area

If your filter housing area is clogged with debris, it may block the flow of water and cause leaks. This problem is particularly common in devices that have a threaded housing area for their cartridges.

The debris gets stuck between the thread and causes leaks.

To clean the housing area, remove the filter from your faucet filter. In the case of a filter pitcher, empty the pitcher, remove the lid, and take the filter out.

Scrub the housing with soapy water and a toothbrush until all the dirt is removed. Wipe along the thread and slots to remove any grime. Dry thoroughly and run the housing under water to remove any soapy residue.

You can also remove the cartridge from your filter pitcher and shake it vigorously until you hear the granules shifting inside. Reinsert after rinsing the housing. This will also optimize water flow. 

5. Lever Not Closing Properly

If the leak is from the point of the on/off lever of the faucet filter, uninstall the device from the faucet and reinstall it.

Remove the device by turning the threaded mounting nut clockwise. Once this is done, remove the mount cover and twist the filter cartridge into place.

While reinstalling, take care to ensure that the device remains horizontal throughout the process and that the PUR logo faces you. Push the lever firmly and turn it on and off a couple of times.

6. Incompatible Adapter

Your PUR faucet filter comes with a set of adapters and washers. Using the wrong adapter with your faucet can cause water to leak at the joint between your tap and filter device.

Depending on your plumbing fixtures, you may need an adapter for externally threaded faucets, internally threaded faucets, or no external adapter at all. Try installing your faucet filter without any adapter. If that doesn’t work, use one of the adapters provided.

PUR sells two sets of adapters – A and B for externally threaded faucets, and C and D for internally threaded faucets.

Pick the most appropriate adapter that matches your faucet threading. Insert the black rubber washer into the threaded end of the adapter for a snug fit.

Tighten the adapter and washer firmly and install the faucet filter. Do not use pliers or other tools to fasten the adapter. Finger-tightening will do.

Make sure you use only the washer of the new adapter – feel around the faucet for the old washer and remove it before inserting the new adapter-washer combo.

Note that if none of the provided adapters fit your faucet, you can contact PUR for a free adapter that fits your plumbing.

7. O-Ring Problems

The O-ring is a rubber or plastic ring that is fixed on the filter cartridge. It is supposed to seal a plumbing joint so that no air or water escapes through it. However, incorrectly fixed O-rings can cause your filter to leak.

Each faucet filter cartridge comes with its own O-ring.

Once you remove the cartridge, make sure that the O-ring sits snugly, and thread it around the faucet. While handling the O-ring, do not stretch or squeeze it too much.

In case you suspect a faulty O-ring in a fairly new cartridge, you can buy a replacement ring online (after specifying the model and dimensions of your cartridge).

If your cartridge is old and nearing its replacement date, consider changing it entirely.

8. Filter Too Tight

Water may overflow from the filter if the cartridge is wound too tight. While installing the cartridge into the device, do not keep turning the filter clockwise AFTER you have heard a click.

Unscrew and screw it again until you hear the click.

9. Incorrect Pouring Method

This applies to the PUR filter pitcher. If you find that unfiltered water leaks out of the pouring tray when you tip it to pour, you may need to correct your technique.

Make sure to completely drain the pour tray before you pour filtered water out of the pitcher. This prevents spills and mixing of filtered and unfiltered water.

10. Valve Leaks

If you find that the valve leaks on your filter pitcher’s dispenser, this may be due to the indicator lights in sleep mode.

Reset the light by pressing and holding it for 5 seconds.

11. High Water Pressure

High water pressure can put undue stress on your faucet filter and cause leaks. High water pressure on the source also exacerbates leaks if your device has not been installed properly in the first place.

To prevent this, do not turn your faucet to a full stream if you suspect high water pressure. Install your device properly.

12. Damaged Filter

A worn-out filter can cause leaks because of mineral damage or clogging. If the water supplied to your house is hard, your filter may be susceptible to scale buildup from calcium and magnesium.

Water with high sediment content can also clog your filter. If this is the case, consider replacing your filter more often.

Things To Keep In Mind

  • Identify the point of leakage so you can determine the best solution.
  • You may need to replace the cartridge more often if your tap water is hard and has more sediments. A clogged filter is more prone to leakage.
  • Always flush the filter before first use. For the faucet filter, run cold water in filtered position for 5 seconds before each use. 

Water Purification Guide also has information about PUR filter lights, and how they works, available here.

Russell Singleton

Russell has a Bachelor of Science (Environmental and Marine Geoscience) with Class I Honors. He is currently completing his doctorate in science and is passionate about all earth processes, especially isotope geochemistry and paleohydrology.

Recent Posts