Reverse Osmosis System Has Low Water Pressure? All Fixes Here!
Written by: Gene Fitzgerald // Last Updated: May 10, 2023
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There are various reasons why a reverse osmosis system may have reduced water pressure. It could be due to a clogged filter element, a ruptured storage tank bladder, or even just a closed valve.
Most of the issues are simple fixes, and the most challenging part might be identifying which of the issues you actually have!
This article will discuss the most probable causes for reduced RO system water pressure and how to fix them.
Contents
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Key Takeaways
There are various reasons why your reverse osmosis water pressure might be low and various ways to fix it:
- Low Feed Water Pressure – Install a booster pump.
- Feed Water Is Too Cold – If your feedwater is lower than 40 degrees, heat the water lines near your RO system.
- A Clogged Reverse Osmosis Membrane – Replace.
- Another Clogged Filter Element – Check and replace the filters if needed.
- Some Other Clog or Kink – Manually adjust kinks or bends in the tubing and clean blockages from lines with a metal brush or cleaning tool.
- RO Tank Pressure Issues – Empty the tank and recalibrate it to a psi of between 6 and 8 psi.
- A Ruptured Air Bladder – You will need to replace the entire tank.
- Air Lock – Open the RO faucet and tilt the system, which should help release the trapped air.
- A Closed Valve – Ensure all the system valves are in the on position.
Why Does My Reverse Osmosis System Have Low Water Pressure?
Why does my reverse osmosis system have low water pressure, you ask?
First of all, reverse osmosis systems have lower output water pressure and slower flow rates than what you might be used to from a regular kitchen faucet, but sometimes it is low enough to warrant that something is wrong or there is a sudden change in the pressure.
This is really common! Luckily, there are a few simple ways to troubleshoot a low-pressure RO system, identify the issue, and fix it yourself.
Make Sure Your RO Storage Tank Isn’t Empty
Before looking for a problem possibly in the wrong place, best to check that your water tank is not empty! You should be able to tell by the weight; an empty tank won’t weigh much. Ask yourself if there is a chance you used all the RO water before the tank had a chance to refill. If this is the case, simply let it sit a while to fill again!
How to Fix Low Reverse Osmosis Water Pressure
If it isn’t the tank, then it is probably a pressure issue, but it could be due to numerous factors, so let’s go through them.
Low Feed Water Pressure
The pressure of your feed water will greatly affect the pressure of your reverse osmosis system. Make sure your feed water pressure is above 40 psi at a minimum, but better if it is 60 psi. Anything less than 40 and the system won’t be able to function correctly.
You can check the feed water pressure by measuring it with a pressure gauge, and if it needs to be increased, time to look at installing a booster pump or adjusting the pressure regulator in your home.
Feed Water Is Too Cold
Reverse osmosis systems work best when the water temperature is between 40 and 100 degrees, ideally at 77 degrees Fahrenheit. If the water is too cold, water output slows considerably (you may notice the changes in winter vs summer). This is because cold water is more viscous than warm water and moves more slowly.
If your feed water is lower than 40 degrees, you may need to find a way to heat the water lines near your RO system. Some do this simply by installing a heater near it for the cooler months.
A Clogged Reverse Osmosis Membrane
A clogged RO membrane can affect water flow/pressure from your RO faucet. If your water is high in contaminants and you haven’t been on schedule with filter replacements and system maintenance, then debris could clog your membrane and block the water from being filtered in the first place.
If you have a clogged reverse osmosis membrane, you will need to replace it, possibly along with the other filter elements, and thoroughly clean the system.
Another Clogged Filter Element
Most RO systems have more than one kind of filter, and it could be that another filter component is clogged and not allowing the water to flow as it should. Check the pre and post-filters, replace them if needed, and see if that fixes the issue.
Some Other Clog or Kink
Anywhere in the RO system could have some kind of clog or debris build-up, especially considering the narrow water lines. This is less likely to happen if your filters are replaced on schedule, and you regularly clean the system. To clear blockages, you need to remove the water lines from the system and scrub them with a clean pipe cleaner or other such tools.
Kinks or bends can happen too, and that just requires a visual inspection and straightening anything out with your hands.
RO Tank Pressure Issues
If your tank has issues regulating pressure, that will be reflected in the RO faucets’ water output. You may need to empty the tank and recalibrate it to a psi of between 6 and 8 with a pump. If the tank pressure drops even after recalibration, it may be an issue with the tank bladder.
A Ruptured Air Bladder
A ruptured air bladder might be causing pressure issues in the tank. If there isn’t any air in the bladder, there isn’t anything to push the water out. The only cure for a ruptured air bladder is the replacement of the whole tank, as it cannot be opened up to repair.
You can check by waiting for the tank to fill up, then filling a glass with 8 ounces of water. If there is a sudden drop in the water pressure once it gets to 8 ounces, it probably means your tank bladder is ruptured.
Air Lock
You may have an airlock in your reverse osmosis system. An airlock is caused by air bubbles trapped in the water lines or elsewhere in the system. To fix this, open the RO faucet and tilt the system. This should help to release the trapped air.
A Closed Valve
You may have simply knocked a valve closed when you were under the kitchen sink at some point! Look to ensure that all the system valves are in the on position.
Further Reading:
How to Measure Water Pressure in a Reverse Osmosis System
The best way to measure the water pressure in a reverse osmosis system is with a pressure gauge right before the RO membrane. This will tell you exactly how much pressure is going to the membrane so you can adjust it if needed. If the pressure is too low, the system won’t be able to work properly.
You could also check the GPD (gallon per day) rate of your RO system as listed by the manufacturer and compare it with what you are getting over 24 hours.
Is Low Pressure Normal?
It could be that low water pressure is simply the norm for you. Some households just have better water pressure than others! Plus, reverse osmosis systems do have a slower water flow rate than regular tap water.
If your household water pressure is below 40 psi, it should be adjusted, or the RO system won’t work properly.
How to Use an RO Booster Pump to Increase Water Pressure
An RO booster pump increases the water pressure of only the reverse osmosis system, adjusting the system’s water output, reducing wastewater, and increasing the ability to filter contaminants.
While municipal water supplies typically have enough water pressure to sustain an RO system, installing a reverse osmosis booster pump ensures the system runs effectively regardless of incoming water pressure. The downside is it does require electricity to function.
Most booster pumps also come with a pressure switch, so if the tank pressure reaches a certain point, the booster pump will switch off. One of these pumps is suggested for a water supply that sits at 40 psi or below. A specific RO booster pump is also cheaper than purchasing one for your whole house, though an entire house option might be nice if you want more water pressure in your shower too!
Installing a booster pump is easy to do yourself with a few tools and a bit of patience.
If you have any thoughts about the question, why does my reverse osmosis system have low pressure, please don’t hesitate to leave a comment below!
About the Author Gene Fitzgerald
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