Water Purifier Failures and Solutions

The water purification systems you use in your home or office, provides an indispensable comfort for access to clean water; however, technical problems may occur over time. Water purifier malfunctions and solutions to be informed about, both protects your budget and saves you the trouble of calling a service in every little problem. The most common problems encountered by users such as "no water from the purifier" or "the device is making noise" can usually be solved with simple methods that can be applied at home. In this guide, we will examine in detail how you can improve the performance of your device, how to adjust the tank pressure and when to replace which parts (membrane, check valve, etc.) from a technician's point of view (EEAT).

The Most Common Failures Encountered in Water Treatment Devices

Water purifiers are systems that operate on hydraulic principles and incorporate many components (filters, tanks, valves). The residential sector accounts for approximately 70% of the total global water treatment market share, which means that breakdowns are most common in the home environment. Below, we have categorised the most common types of faults that users search for and request service.

1. No Water Coming from the Water Purifier (Why No Water Coming from the Purifier?)

If there is no water coming from the water purifier when you open the tap, there are basic points to check before you panic. This situation usually indicates that the system is completely blocked or the water supply is cut off.

• Mains Water and Valves: Firstly, make sure that the main water valve and the blue ball valve at the inlet of the device are open. If the mains water is cut off, the water in the tank of the device may also be exhausted.
• Hose Breaks: Check hoses behind the appliance or under the counter for kinks. A kinked hose can completely stop the water flow.
• Clogged Filters: If the pre-filters (sediment and carbon) have not been replaced for a long time, they may be completely blocked by mud and sediment. In this case, water cannot reach the membrane filter.

2. Water Purifier Gives Little Water (Why Does Water Treatment Water Flow Less?)

One of the most common complaints of users "water is flowing less from the purifier" is the problem. If the water purifier gives little water, the problem is usually related to tank pressure or membrane blockage.

• Low Tank Pressure: Inside the water treatment tank, there is a cushion of air that pushes the water to the tap. This air decreases over time. If the water flows like a thread even though the tank is full, it means that the air pressure of the tank has dropped below 6-7 psi.
• Membrane Blockage: The membrane is the main part that determines the production rate of water. A membrane with clogged pores fills the tank very slowly, which reduces the flow rate of water from the tap.

3. Water Purifier Waste Water Does Not Stop

Under normal conditions, when the tank is full, the system should automatically switch off and the waste water should be cut off. If the water purifier does not stop the waste water and constantly throws water into the drain, this causes a serious waste of water and an increase in the bill.

The main cause of this problem is usually "Shut-off Valve" (Four-way valve) or "Check Valve" malfunction. Shut-off valve is responsible for cutting the mains water when the tank is full. When this part fails, even if the clean water tank is full, mains water continues to enter the system and goes directly to waste. In conventional systems, approximately 2-2.4 litres of waste water for 1 litre of clean water is normal; however, uninterrupted flow is a sign of failure.

4. Water does not fill the water purifier tank

When you open the tap, it takes very little water and if the water runs out immediately, the water purifier tank may not be filled with water. The technical reasons for this are:

• Low Mains Pressure: For reverse osmosis systems to work efficiently, the mains pressure must be at least 3-4 bar. If the pressure is low, water cannot pass through the membrane and cannot reach the tank.
• Tank Valve Closed: Make sure that the small valve on the tank has not been accidentally turned to the closed position.
• Burst Membrane (Shamrel): If the rubber bubble inside the tank is punctured, the tank cannot create pressure even if it receives water. If the tank is extremely heavy when you lift it from its place but does not give water, it means that the membrane inside has burst.

5. Water Purifier Dripping and Leaking Water

Seeing a puddle of water under the countertop indicates a leakage problem. Water dripping problems are usually caused by loosening at the connection points.

• Elbow and Unions: Check the elbow (L-piece) connections in the filter vessels. They may be loose or cracked.
• O-Ring Gaskets: If leakage has started after filter replacement, the black O-ring gaskets inside the filter vessels may have been displaced or crushed.
• Housing Cracks: Excessive pressure (water hammer) can cause hairline cracks in the filter housing that are difficult to see.

6. Water Purifier Makes Sound (Why Does Sound Come from the Device?)

If the device emits "click click", "whistling" or "whistling" sounds during operation, this is caused by air entering the system or pump failure.

• Trapped Air: Air may remain in the system after a new filter change. Leaving the tap open and allowing the water to flow for a while discharges the air.
• Pump Problems: In devices with pumps, wear of the bearings in the pump head or resonance of the pump causes noisy operation.
• Waste Water Restrictor: When the flow restrictor in the waste water line becomes blocked, water may whistle as it passes through.

7. Treatment Water is Calcareous, Cloudy or Foaming

Users are sometimes concerned about the appearance of water. But not every turbidity is a malfunction.

Cloudy/White Water: Micro air bubbles in newly installed filters give the water a milky white appearance. If the water becomes clear from bottom to top when it is left in the glass for a minute, this is completely harmless and temporary.

Calcareous Water: If the water is really calcareous (leaves sediment in the kettle), the membrane filter has lost its function. Hard water conditions can shorten membrane life by 30%.

8. Water tastes bitter or has an odour problem

If the treated water tastes bitter or has an odour, the culprit is usually the flavouring (post-carbon) filter or membrane filter.

Post-Carbon Filter: This filter, made of coconut shell, gives the water its final flavour. At the end of its life (about 12 months), the water tastes bland or bitter.

Bacteria Accumulation: In devices that are not used for a long time, bacteria can grow in the filters, which causes odour.

Fault Detection: Water Treatment Spare Parts and Functions

To correctly identify the source of the malfunction, it is necessary to know what the parts inside the device do. Below we have detailed the failure symptoms of critical parts.

Water Treatment How to Understand Check Valve Failure?

The check valve is a small part, usually located at the membrane outlet, which allows water to flow in one direction. If the check valve fails, the clean water accumulated in the tank escapes back and is discharged from the waste water line.

Symptom: If your tank is full but the appliance is constantly switching on and off (running sound at short intervals) and water continues to come from the waste water hose, the non-return valve is faulty.

Water Treatment Pump Repair and Continuous Operation Problem

The pump allows water to pass through the membrane in low pressure areas. If the pump runs continuously;

• High Pressure Switch: This part, which should cut off the electricity when the tank is full, may be broken.
• Leakage: If there is a leak somewhere in the system, the pressure does not rise and the pump runs continuously.
• Adapter: There may not be enough voltage to the pump.

When to Change Membrane Filter?

The membrane is the heart of the system. The surest way to know when it is time for replacement is to use a TDS Meter (Water Quality Meter).

TDS value should be 90%-95% lower than mains water.

For example, if your mains water is 300 ppm, treated water should be between 10-30 ppm.

If your treated water is 40 ppm and above, the membrane filter has reached the end of its life and should be replaced.

Practical Home Remedies and Care

There are some do-it-yourself (DIY) solutions you can implement before calling for service.

How to Clean and Bleed the Water Treatment Tank?

The air pressure inside the tank decreases over time and the water flow rate decreases. To correct this:

• Close the inlet valve of the appliance and completely drain the water in the tank from the tap.
• Open the blue valve cap on the front or bottom of the tank.
• Press air into the valve with a bicycle pump (it is recommended to have a pressure gauge).
• The ideal pressure should be 6-7 psi (approximately 0.5 bar).
• If water comes out of the tap while pumping air, continue until the water in the tank drains.

Important Warning: If water comes out instead of air when you press the valve, it means that the diaphragm (membrane) inside the tank has burst. In this case, pumping air is useless, the tank must be replaced with a new one.

Filter Change Periods and Monitoring

Replacing your water treatment filterson time prevents the breakdown of other expensive parts (pump, tank). You can refer to the table below:

When is Professional Technical Service Required?

It may not be possible to solve every malfunction at home. Especially in electrical components and structural problems, expert support is essential.

• Electricity Leakage: If you feel an electric shock when touching the appliance, unplug it immediately.
• Pump Repair: Pump head replacement or winding problems require technical expertise.
• Continuous Water Leakage: If the leakage continues despite replacing all gaskets, there may be invisible cracks in the housing body.

The global water purifier market is expected to show huge growth from 2025 to 2034, which means that professional service networks and spare parts availability will increase.

Failure Symptom and Solution Matrix

By regularly maintaining your water purifier and following the tips above, you can consume healthy and clean water for many years. If you are hesitant about troubleshooting, please get support from an authorised service.

Frequently Asked Questions (FAQ)

We have compiled the most frequently asked questions and clear answers of users in search engines.

How to reset the water treatment?

Resetting process varies according to the model of the device. Manual (mechanical) water purifiers do not have an electronic reset process; it is sufficient to physically change the filter. However, in digital display or smart devices, the 'Reset' or filter button on the panel must be pressed and held for 3 to 5 seconds to delete the warning after the filter change. In some systems, unplugging the device and plugging it back in after waiting 10 seconds resets the system.

How to understand water treatment membrane failure?

There are 4 basic symptoms that indicate that the membrane filter has failed:

• The taste of treated water becomes bitter or calcified (lime scale in the kettle).
• Excessive decrease in the flow rate of the water coming from the treatment tap or dripping.
• The device's waste water discharge never stops even if the tank is full.
• It is determined with a TDS metre; if the conductivity (TDS) value of the treated water exceeds 40 ppm, the membrane filter has lost its function.

What happens if air is pumped into the water purifier tank?

Inside the water purifier tanks there is an air-filled rubber balloon (membrane membrane) to push the water towards the tap. Over time, this air may decrease. If air is pressed from the air valve of the empty tank (with the help of a bicycle pump) around 6-7 psi, the internal pressure of the tank is balanced and the pressure of the water flowing from the tap is restored. However, if the membrane inside the tank has burst, the air cannot hold and is thrown out of the tap with the water. In this case, pumping air is useless, the tank must be completely replaced.

Sources

https://www.nsf.org/consumer-resources/articles/water-filters-testing-treatment

https://www.grandviewresearch.com/industry-analysis/water-purifier-market

https://www.who.int/teams/environment-climate-change-and-health/water-sanitation-and-health/water-safety-and-quality