Reverse osmosis (RO) systems are fantastic at filtering out most common contaminants from water. Sometimes, however, they can generate loud and unusual noises that can be concerning for homeowners. In this article, we will explore the reasons why your reverse osmosis system might be loud and provide solutions to address each problem.
The most common reasons for your RO system to be loud are air bubbles in the system, clogged or dirty filters, faulty pressure regulators, loose connections, missing or worn-out membrane, faulty motor, and water hammer effect or water supply pressure fluctuations.
In this post, we will be discussing each of these reasons in detail, and describe some tell-tale signs that to identify the problem with your RO system. We will also talk about some common solutions you can try to help reduce the loud noise your RO system is making.
Let’s get started.
Is my Reverse Osmosis system producing abnormally loud sounds?
Before getting into the potential causes of a loud reverse osmosis system, it is important to first work out if the sound your RO system is producing is actually abnormal. This is because there are some normal sounds that an RO system may produce during operation.
While these systems are generally designed to operate quietly, there are a couple of sounds that should be considered normal:
- Trickling or flowing Water: As the water is being filtered, you may hear a gentle trickling or flowing sound of water moving through the system. This sound is often soft and consistent, and its totally normal – the system is probably functioning properly.
- Low humming: Most reverse osmosis systems use a pump or motor to generate the pressure needed for filtration. A low humming sound is typically present when this pump or motor is in operation. This sound should be relatively quiet and steady, without any noticeable fluctuations or irregularities.
Sounds outside of this, like a loud whining, sputtering, dripping, hissing, screeching, or a machinery-like clanking or grinding could mean there is something wrong.
Seven Reasons Why Your Reverse Osmosis System is Loud
1. Air bubbles
When you first install your reverse osmosis system, there may be some air bubbles trapped in the filter’s tubing. It is going to take some time before these bubbles get fully cleared, and this could obviously cause a bubbling sound.
Air bubbles may also escape into your reverse osmosis system while replacing the filter.
A gurgling or bubbling sound is the biggest indicator of air bubbles in the system. This gets especially pronounced when you are withdrawing water, or if there is an active movement of water within the system at any given time.
To fix this problem, you can take the following steps:
- Start by shutting off the water supply to the RO system.
- There is usually an air valve or air purge valve on your system, which you need to locate using your product manual for help.
- Then, simply open the valve and allow any trapped air to escape.
- Once the air is released, close the valve and turn the water supply back on.
- Run the system for a few minutes to ensure the air bubbles have been eliminated.
2. Clogged or dirty filters
A reverse osmosis system consists of various types of filters to remove impurities from the water. Over time, these filters can become clogged or dirty, leading to restricted water flow. And whenever the flow is restricted, it can produce noise.
In most cases, whenever the problem is a clogged or dirty filter, you will hear a distinct hissing or whistling sound. Another way to diagnose the issue is to simply check when the filter was last replaced, and to evaluate when the filter was due for a change.
To solve the issue, take the following steps:
- Start by turning off the water supply to the RO system.
- Depending on your specific model, locate the filter housing and remove the cartridges. The specific way to do this depends on the model, and we strongly recommend going through the user manual to know the correct way to do this.
- Inspect the filters for any signs of debris or clogs. It may appear as brown, dark green or even black stains or debris over the filters.
- If they appear dirty, replace them with new filters following the manufacturer’s instructions.
- Once the new filters are installed, turn the water supply back on and check if the noise has stopped.
Doing this process may introduce air bubbles in the system, meaning the whining noise can be replaced by the gurgling sound of bubbles. Refer to the previous point on how to solve this issue.
3. Faulty pressure regulator / High inflow pressure
In many houses, RO systems are directly connected to the central water supply. Sometimes, this central supply can be at very high pressure, whereas the pressure level in your house may be low. This change in pressure means water will flow into the RO system very rapidly, which can create a hissing, banging or vibrating sound.
Sometimes, the water may produce a hammering sound as well due to a sudden pressure fluctuation. This is commonly known as the ‘Water Hammer Effect’.
To combat this, many RO systems have a pressure regulator. As the name implies, its job is to regulate the water flow into the RO system.
A faulty pressure regulator can therefore cause irregular water flow and increased noise levels in a reverse osmosis system. If you hear banging or vibrating sounds, it may indicate an issue with the pressure regulator.
You may take the following steps to solve this issue:
- Like with the previous issues, begin by shutting off the water supply to the RO system.
- Locate the pressure regulator, which is typically connected to the water inlet line.
- Inspect the regulator for any visible damage or signs of wear.
- If you notice any issues, such as leaks or loose connections, consider replacing the pressure regulator. Consult the manufacturer’s instructions or seek professional assistance if needed.
If your RO system does not have a pressure regulator at all, it is necessary that you first consult a professional to check the inflow pressure in your home, and then have a regulator installed if needed.
Sometimes, the pressure in the inflow water may itself fluctuate. This will result in intermittent hissing noises. Having a pressure regulator is, again, the main solution for this.
4. Loose connections or fittings
Whenever any machinery consists of moving parts, it is important for the connections and fittings to be perfect for there to be smooth functioning – and the same applies to RO systems.
An RO system will consist of several parts: the inflow recipient, the pressure regulator, multiple filters, membranes, and an outlet, if not more. If any of these are not in perfect alignment with each other, not only can it produce unwanted noise, but can also compromise the overall filtration efficacy of your RO system.
Usually, loose connections or fittings within the reverse osmosis system result in vibrations and rattling noises. If you hear a rattling or shaking sound, it is likely caused by loose components.
You may follow these steps to solve this issue:
- Carefully inspect all the connections and fittings within the RO system.
- Try gently moving each component. If fitted well, no part should appear freely movable.
- If you identify any loose connections, tighten them using appropriate tools. We advise you to be cautious not to over tighten here, as it may cause damage to some delicate parts of the system.
- After securing all the connections, run the system to check if the noise has been eliminated.
5. Worn-out Membrane
The membrane is a crucial component in a reverse osmosis system, responsible for filtering out impurities from the water. Over time, the membrane can wear out or become damaged, leading to reduced efficiency and increased noise levels.
If you hear a squealing or high-pitched sound, it may indicate a worn-out membrane.
Solving this issue, thankfully, is quite easy:
- Start by shutting off the water supply and depressurizing the RO system.
- Using the user manual, locate the membrane housing and carefully remove the membrane cartridge.
- Next, inspect the membrane for any visible signs of wear, such as cracks or tears.
- If the membrane appears worn-out or damaged, replace it with a new one. We advise caution at this stage, as certain manufacturers may not entertain you changing the membrane/filters yourself, and may instead offer professional help for the warranty to be maintained.
- Once the new membrane is installed, turn the water supply back on and check if the noise has diminished.
6. Improper drain line installation
Reverse Osmosis systems have something called a ‘Drain Line’, which is essentially responsible for carrying the wastewater away.
If the drain line is improperly installed or has a partial blockage, it can result in abnormal water flow. And as we have learned so far, any abnormality in water flow can result in noise.
In this particular case, you can expect to hear gurgling or bubbling sounds whenever water passes through the drain line.
The drain line, even when installed properly, may sometimes move from its place. This is often the case when the drain line is under your sink, and you accidentally end up moving it when retrieving or placing something else from under the sink.
To solve the issue, these steps can help:
- Check the drain line for any kinks, clogs, or improper installation.
- Listen to the drain carefully to see where exactly the noise is coming from. Ensure that the drain line has a proper air gap to prevent backflow.
- If you notice any issues, reposition the drain line or remove any blockages.
As always, consult the system’s manual or seek assistance from a professional plumber if you do not feel confident in doing this yourself.
7. Motor or pump issues
In a reverse osmosis system, the motor (or the pump) is responsible for generating the pressure needed for filtration. If this starts malfunctioning or gets worn out, it can produce unusual or loud sounds, such as grinding, screeching, or excessive humming.
If you suspect an issue with the motor or pump, we advise contacting the manufacturer or a professional technician who specializes in reverse osmosis systems. They can assess the motor or pump and determine whether repair or replacement is necessary.
Attempting to fix these components without proper knowledge may cause further damage, and may render your warranty void in some cases.
Frequently Asked Questions
When should the RO membrane be replaced?
Your RO membrane should be replaced whenever it stops functioning well.
The best way to know this is by consulting your manufacturer or the user manual.
Sometimes, this can also be evident through decreasing flow of water, or even through complete cessation of water flow.
Do Reverse Osmosis systems need high pressure?
Reverse Osmosis systems often function at high water pressure (100-800 psi), which forces water through a semipermeable membrane and removes impurities in the process.
For this, there is usually a pump inbuilt into your reverse osmosis system, along with a pressure gauze.
Does reverse osmosis remove bacteria?
Reverse osmosis uses advanced, semi-permeable membranes that can filter out even tiny mineral molecules. If your reverse osmosis system has all the filters it needs and is well maintained, it is safe to assume that it can remove most forms of bacteria safely.
Final Thoughts
While a reverse osmosis system can normally produce soft, low sounds, a loud reverse osmosis system can be concerning. In many cases, the issue is related to various factors which ultimately cause the water to flow abnormally, thereby producing abnormal sounds. Most of these problems can be resolved by addressing specific issues within the system as we have explained here, but one must remember to always follow the manufacturer’s instructions and seek professional assistance if needed.
