Why Reverse Osmosis Water Flow is Slow?

If the water coming out of your Reverse Osmosis (RO) faucet seems to be slower than normal, or slower than you think it should be, here are six reasons that can make your under sink RO have slower water production:

1. Clogged RO Membrane Slows Water Flow:

If you forget to change RO membrane, with time your system will produce less and less water. Reverse osmosis membranes are fragile and can ro-membrane.jpgbecome fouled if not changed often. Trying to fill your tank with a fouled membrane may take 4-6 hours, rather than the usual 2-4 hours. Generally, RO membranes only need to be replaced every 24 months. We suggest setting a calendar reminder to buy a reverse osmosis replacement membrane

2. Pressure in Tank Might be Low:

Slow water flow rates might be a result of low pressure inside the RO tank. Reverse Osmosis tanks should have pressure of 7 to 8 psi without any water in the tank. To check your pressure, locate the Schrader valve, typically covered by a blue plastic cap, on the side of the tank near the bottom. After removing all the water from the tank, use a pressure gauge to determine the pressure in the tank. If low, add air with a pump until you have 7-8 psi. Be careful to only add a small amount of air at a time, as too much pressure can rupture the air bladder.

3. Ruptured RO Tank Bladder:

If you only get about one cup (8 oz) of water out of your RO faucet at normal water pressure, and then the water promptly trickles down to a very small stream, this typically is a sign the air bladder in the storage tank as ruptured. Unfortunately the air bladder cannot be repaired and the only way to resolve the issue is to replace the storage tank. Replacement tanks can be found here

4. Clogged Filters Can Slow RO Water Flow :

If your 5-stage RO system water is slow, you probably need to change your sediment, carbon, and polishing filters, in addition to the RO membrane dirty-water-filters-slow-RO-flowmentioned above. Clogged filters are probably the most common reason for reverse osmosis slow water flow.  The filters should be changed annually, unless water conditions and contaminants present require more frequent filter changes (like every six months instead of 12).

5. Kink in Water Line Can Disrupt Flow:

Make sure there are not any kinks in the water line, which would slow water production. And while you're inspecting your system, double check that the water supply line valve is in the fully open position.

6. Loss of RO Water Pressure:

You may have temporary loss of water pressure. An RO system needs a minimum of 40 psi to operate properly, but preferably 60 psi. If all of your household faucets seem to have low water pressure, it may be that your local water utility company is temporarily flowing as lower pressure. Often, higher water pressure will return if you wait a bit. If higher water pressure does not resume, report the issue to your local water utility company.

Additional RO Slow Water Flow Troubleshooting Assistance

You might want to consult our troubleshooting guide or call a water treatment specialist in your area for additional assistance. For products purchased through espwaterproducts.com, customer support is available Monday through Friday 8 am to 5 pm (Central time) at 877-377-9876. Have your customer or invoice number ready.

NOTE: "filter bundles" are a convenient way to take care of annual filter replacements. These annual replacement kits include everything you need for annual filter replacements, and often save you time and money. Find your filter bundle by first identifying your RO system brand/model.