Troubleshooting PUR Water Filter Problems (Slow & Not Working)

PUR water filters offer homeowners fresh and impurity-free drinking water. PUR filtration systems are designed to reduce 70 contaminants from water, including mercury, lead, and various pollutants, by using technology that filters water over natural minerals. 

They come in a variety of styles such as faucet attachments or standalone pitchers or dispensers. At times, these filters have problems that result in slow or non-working filters that generally are easy to troubleshoot and fix.

PUR water filters tend to have problems due to an issue with the filter itself or the housing unit. It could have trapped air bubbles, blockages or clogs, damage from hot water or minerals, too high or low water pressure, or problems related to usage and installation. Thankfully,  these issues are easy to fix by flushing out, replacing the filter, or cleaning.

Types of PUR Filtration Systems

Faucet Systems

A PUR filtration faucet system attaches to the end of a sink faucet for on-demand filtered water. When the sink is turned on, the pressure pushes water into the faucet’s head. 

With the push of a button or tab, the consumer can divert water for filtered water or bypass the filter for using tap water.

Faucet Systems

One model of PUR faucet systems comes Bluetooth enabled. This allows the user to sync a phone app with the faucet to track the consumption of water and filter usage.

This type of filter is bulky yet easy to attach without the use of tools. This style does not work with handheld, pull-out, or pull-down faucets.


BPA-free PUR pitchers use gravity filtration which is a passive way to move water through a filter. 

The top of the pitcher is filled with tap water, and then gravity pulls water down through the filter into the collection basin. 

Generally, it takes up to 15 minutes for all of the water to move through the filter.

Pitcher models range in size, holding from 7 to 11 cups of water, and are designed to fit in refrigerator doors or on shelves.


They have locking lids to prevent spills when pouring water, with a light to indicate when it is time to change the filter. 

With the filter removed, the pitchers are dishwasher safe.


Like the pitcher model, PUR filtration dispensers use gravity filtration. However, they are much larger, filtering large batches of water of up to 30 cups. 

The collection basin holds 18 cups of water and retains up to 12 cups in the filter basin. As water is drawn out from the collection basin for consumption, the water sitting above moves down through the filter.


These BPA-free dispensers are designed to sit on a refrigerator shelf with the spout facing outwards. The pulldown tab and spout are easy to operate to get a glass of water. 

Dispensers have a light to indicate when it is time to change the filter, and it is dishwasher safe with the filter removed.

Causes of PUR Water Filter Slow Flow Rate or Not Working

There are several causes of why a PUR filter has a slow flow rate or is not working. These typically are related to issues with the filter itself, installation, or improper use. 

Let’s take a look at these issues and how to fix them.

Air Bubbles In The Filter

A common cause of air filtration is the presence of air bubbles in the filter. This is most often seen in PUR faucet filter systems, however, it can happen with any model.  

Unlike gravity filters, water only moves through when the faucet is turned on. This means that air can move into the filter in between uses.

Air bubbles can also become trapped if the pressure of water is too high (more on that below).

Thankfully, this is an easy fix.  

What To Do

  1. Refer to your user manual if necessary, and remove the unit from the faucet. Then remove the water filter cartridge from the unit.
  2. Place the filter into a large jar or bowl of water, completely submerging it.
    1. You may need another bowl on top to hold the filter down in the water.
  3. Let the filter soak for 15 minutes.
  4. While the filter is soaking, clean the mounting compartment that holds the filter.
    1. Use a soft toothbrush and warm water to scrub and rinse away any debris inside.  
    2. For stubborn spots, use a solution of three parts cold water with one part vinegar to scrub and then rinse clean.
  5. Remove the filter from the water and gently shake off excess water. You can gently tap it against the sink if your sink is clean.
  6. Hold the filter upright, and run cold tap water over it for 30 seconds.
    1. Never use hot water, since this can damage the filter.

Filter Housing Blockage

The part that holds, or houses, the filter can have a blockage from trapped sediment or debris in the casing’s threads. 

This is commonly seen in PUR filters that screw into place with external or internal threading, but it is possible with any model.

This debris or build-up can damage PUR filters resulting in slow- or no-draining filters.

What To Do

Every time you replace a new filter, the housing area should be thoroughly cleaned. 

Even if it is not time to replace it, use this method to see if your filter flow improves. 

  1. Remove the filter and housing. Inspect the housing threads for any debris or sediment. 
  2. Use a soft toothbrush to scrub the threads and rinse clean with water.
    1. If the debris is stubborn, use 3 parts water with 1 part vinegar to scrub, and then rinse clean.
  3. Allow the housing to thoroughly dry and then inspect it again for debris before putting everything back together.

Old Filter That Needs Replacing

A filter is designed to trap and hold onto impurities from the water. As the filter fills up with these over time, it will become “full”. 

This means water will not be able to pass through as quickly.

What To Do

You must pay attention to the PUR filtration system’s filter notification light. This light is activated by a sensor in the unit. Change the filter when it tells you to do so.

To prevent any delay in replacing the filter, always have a new one on hand ready to go. Many replacement filters are available in multi-packs.

Refer to your user manual for the typical time frames for replacing the filter. However, this will vary spending on how much you use the system.

In general, PUR faucet filters should be replaced after using 100 gallons of water (approximately 3 months). 

PUR pitcher and dispenser filters should be replaced after 40 gallons of water (approximately 60 days).

This video demonstrates how to replace a PUR faucet filter:

PUR Faucet Water Filter Replacement – HOW TO REPLACE

Clogged Filter

If a pitcher filter is taking longer than the average 15 minutes, sediment could be the cause.

Tap water that has a large amount of sediments, such as clay, rust, and minerals can clog filters at a faster rate. You will notice that the speed of filtration will slow over time as a result of a high sediment load in the water.

What To Do

The filter is doing its job by removing the sediments, but if you have a higher rate of sediment, you will need to replace the filter more often (as described above). 

You should also make sure to clean the filter housing each time to remove any stuck debris.

If you wish to check sediment levels in your tap water, do the following:

  1. Fill a glass with unfiltered water, and let it sit for 60 minutes.
  2. If there is a high amount of sediment in the water, you will see residue at the bottom of the glass.
    1. If this is the case, you will need to change your filter more frequently. 
    2. Consider buying multi-packs of filters to save money.

Note: If sediment is a major issue, consider installing a whole-house water purification system on your main water line. This will also help prolong the life of your water tank, water appliances, and plumbing by keeping sediments out of them.

Flushing The Filter Incorrectly (Or Not At All)

The filter must be flushed properly before installing it into the housing. 

Filters use activated carbon to absorb contaminants or change chemical compositions for safe consumption. Carbon particles can become dislodged and loose during the manufacturing process. 

These black specks can be seen in filtered water or will clog up the filter. User instructions state that filters should be flushed before use to get rid of loose carbon.

What To Do

How to flush a filter depends upon the type that you have.

For PUR faucet filters, you install the filter, put the tab in the filtered position, and run cold water for 5 minutes. The water should be emptied directly into the sink’s drain, and not used for consumption.

For PUR filter pitchers and dispensers, the filter should be submerged in a bowl of cold water for 15 minutes before installation. You may need another bowl to sit on top of the filter to hold it down. 

Then, you install the filter into the pitcher or dispenser, fill the reservoir, and let it drain through into the collection basin. Discard this water and repeat this one more time, or according to the user instructions.

Hot Water Damage

PUR filters are designed to work with cold water. Running hot water through them will cause damage and therefore improperly working filters.   

Generally, faucet filters should not be used with water temperatures above 100˚F, and pitchers and dispensers over 82˚F.

What To Do

Once hot water damages a filter, water will either flow through too slowly or too fast. A damaged filter will need to be replaced since it cannot be repaired.

Follow user instructions for installing a new filter, and make sure you flush it first (as described above).

Mineral Damage

Water can leave behind limescale which is largely comprised of calcium and magnesium. While these are not unhealthy minerals, they can build up on appliances and plumbing that use water, causing reduced water flow.

These minerals can build up over time within your filtration device and appear as a white-colored crusty layer.

Some PUR filters do not remove these minerals, and therefore the filter housing and compartments can have limescale.

What To Do

If you have hard mineral water, you will need to change filters more frequently as well as clean the housing.  

An alternative solution is to install a whole-house filtration system or water softener, or purchase filters designed to remove these minerals.

Low Water Pressure

A low water pressure issue is related to the faucet style of PUR filtration models. As mentioned, faucet filters use water pressure to remove contaminants.

What To Do

Make sure the tap is opened all the way to get a good flow and pressure of water through the filter.  

If low pressure is an issue throughout your entire house, contact a plumbing professional to evaluate and resolve the problem.

High Water Pressure

High water pressure from your system can also cause problems. The higher pressure creates aeration, which adds air to the water. As a result, air bubbles can become trapped in the filter and slow the filtration rate. 

What To Do

Manually remove air bubbles from the filter, by removing it, and letting it soak submerged in cold water for 15 minutes. Then, run cold water over it for 30 seconds in an upright position.

In the future, make sure to open the faucet all the way to prevent a concentrated high water pressure on the filter.

Incorrect Installation

Incorrect installation of a filter typically happens when someone replaces the old filter with a new one. As a result, the flow slows or stops. 

You need to check that your filter is threaded or clicked in securely.  

What To Do

  1. Take the filter out and make sure all protective caps and packaging are removed.
  2. Make sure that the filter was flushed, or flush it again before reinstalling.
  3. When reinstalling, the filter should twist and click into place.
    1. Any rubber washers (if applicable) should be hand-tightened and secure.


Troubleshooting PUR water filter issues is an easy task. Most of the time the filter needs to be replaced, there is a buildup of debris or sediments, or the housing needs to be cleaned.

By making sure to flush filters before installing them, then installing them correctly in their corresponding housing, you will avoid most issues. 

Purchase replacement filters ahead of time so you have one on hand as soon as the indicator light tells you it is time for a new one.

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