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Installation Guide


  1. Safety Glasses.
  2. Variable Speed Drill with 3/8" Chuck.
  3. 1/4"Drill Bit (3/8" for air-gap faucet).
  4. 1 1/4" Hole Saw (If additional hole is needed in sink for faucet).
  5. Extension Cord, Drop Light or Flashlight.
  6. Teflon Tape, Household Bleach (liquid).
  7. Plastic Anchors & Screws.
  8. Razor Blade, Screw Driver, Pliers, Adjustable Wrench(2).
  9. Pencil & Old Towels.
  10. Basin Wrench, Center Punch & Hammer.
  11. Relton Porcelain Drill Kit (Porcelain sink requiring additional hole)

View Installation Diagram (Chart showing components and connections of 4 stage reverse osmosis system - works for 5 stage reverse osmosis system also)


1.Remove all system components from box and determine the location where the filter housings, tank and faucet will be placed. The Reverse Osmosis (RO) System is designed to fit under most sinks. It is also commonly installed in the utility area of lower levels or basements and the tubing extended up to the faucet and/or ice maker. It can be installed anywhere that will not present a problem of freezing in the winter. Basement installations offer cooler water during the summer months. It would also provide easy access for filter changes and easier connection to a refrigerator icemaker or a second faucet in a bathroom or wet bar. Furthermore, it does not take up valuable space in your kitchen cabinets. It may also be a less worrisome location should a leak develop. In the warm weather areas, an attached garage might offer a suitable location. If it is put under a kitchen cabinet, extra tubing in its connection might be advisable, since you could remove it for filter changes without disconnecting it. However, since most installations are performed under a kitchen sink, this guide will describe that procedure. Think about your installation before you begin. Remember that good access will allow easier filter changing.


2.Install filters and membrane in housings. The white 10" sediment filter goes in the first filter housing. This is the inlet feed water and is the one on the right. The 10" carbon block filter goes in the second filter housing. This is the one on the left. The RO membrane goes in the horizontal housing on top of the RO system. Be sure that all housings are securely screwed tight. The rubber "O Rings" will create a seal when securely tightened.

If you desire to hang the filter housings, use the holes in the filter housing mounting bracket to mark the locations to drill to install (2) mounting screws and screw into side wall. There should be enough clearance below the bottom of the housings, so that you can place a pan to catch water when the filters are being replaced. Hang the filter housings to see if enough room was allowed. Set tank on firm surface. Try to position so that you have best access to shut-off valve on tank and not obstructing shut-off on cold water line. The tank can be set upright or laid on it's side. It can be 100 feet away from the faucet. However, the closer it is to the faucet, the better the flow. Remove and set aside filter housings and tank for now.


When using the "SELF PIERCING TAP" valve on copper lines instead of the optional "screw together" easy tap described below. Make sure to install it in-line after the cold water shut-off valve. Mount and tighten the "self piercing valve" on the copper line in a easy to reach place. Turn the saddle valve clockwise all the way in. This drives the sharp end of a sharp metal pierce into the copper tubing and will pierce a tiny hole. This is the "OFF" position for your new RO system. Leave it like this until later in the installation process. Do not use a tube insert on the incoming water line connection. This could possibly restrict the flow and/or pressure to the some systems and cause it to run continuously, possibly fouling the membrane. Always consult the owners manual.
If using the optional "EASY TAP": Use Teflon tape to wrap the threads of the valve that screws into the side of the easy tap. Screw together and use a wrench to securely tighten. Insert black rubber washer into end of easy tap. Never install on hot water line. Turn off cold water supply to sink faucet. Follow the pipe up from the shut-off valve toward faucet until you reach a coupling nut (may be all the way up to the faucet). Unscrew coupling nut. Screw brass easy tap onto previous location of coupling nut. Hand tighten and then one more complete turn with wrench. Re-attach water line coupling nut to easy tap. The valve on the side of the easy tap is the shut off valve for your new RO system. If the handle is turned perpendicular to the water line, this is the "OFF" position for your new RO system.

Click Here to Order Valves


  1. When tightening easy tap, make sure the tube you are connecting easy tap to is not being twisted. Use two wrenches if necessary, one to hold existing nut and the other to turn the easy tap.
  2. Examine existing cone shaped washer screen, adjust or replace if damaged or worn with new cone shaped washer screen.
  3. Do not use a tube insert on the incoming water line connection. This will restrict the flow and/or pressure to the system and cause it to run continuously, possible fouling the membrane.


  1. Sink With Disposal - Select location to place drain saddle. Best choice is the vertical pipe above the horizontal pipe from garbage disposal. OR Sink Without Disposal - Best choice is the vertical pipe as high above the water level in the trap as possible. The drain line may also run directly into a laundry tub or open floor drain. (Drain line can run uphill and even distances of more than 100 feet.) Try to keep the saddle as far away from the dish washer and waste disposal drains as you can. Do not use the body of the saddle as a guide for your drill. The threads of the drain saddle may be damaged. You do not need a plastic insert on the end of the tube that attaches to the drain saddle.
  2. To install, drill a 1/4" hole (3/8" for air-gap faucet) through one side of the drain pipe. Remove any "burrs" created from drilling. This will help prevent debris from plugging drain hole. Align and center gasket on hole between pipe and drain saddle. Align the hole in the drain saddle with the hole in the drain pipe. Tighten down the drain saddle firmly.

Click Here To Order Drain Saddles


  1. Most sinks have an extra hole for the mounting of additional faucets, sprayers or soap dispensers. If your sink does not already have an additional hole, use the following procedure.

    Determine Location of Faucet Hole. Check underneath sink before drilling, making sure there are no obstructions. If using an air-gap faucet, place faucet so water from air-gap hole on side of faucet will run down into sink if drain tube were to plug. Place an old towel under sink to catch any metal filings to make clean up easy.

    Stainless Steel Sink. Carefully mark the faucet location, making sure it is far away enough from the regular water faucet(s) so that they don't interfere with each other. Look to see if you can tighten the lock nut from below, before you drill a hole. Use center punch to make an indentation in sink surface to help hold alignment of hole saw. Drill a 1 1/4" hole with hole saw. Smooth out rough edges with a file if necessary.

    Porcelain Coated Sink. The manufacturer recommends to have this type of sink professionally drilled because of possibility of chipping or cracking. If you are attempting to drill, use extreme caution. Use a Relton Cutter with adequate cooling lubricant.

    You may also install the faucet directly into the countertop if you do not want to drill the sink. Position the faucet at the location to be drilled to make certain that the end of the spout will reach over the sink. Feel underneath the countertop to make certain there is no obstruction that would prevent proper faucet installation. Drill a 1 1/4" hole for both the air gap and non air gap faucets.

    See more information on air gap faucets

  2. Installing Standard Non-Air-Gap Faucet:

    (1) Once the hole is prepared, assemble those parts of the faucet that belong above the sink. First, the faucet spout. Some faucet spouts have threads, most do not. It is not necessary to tighten the faucet spout. It is preferable to let it move freely. Then you can move it out of the way when you wish. Insert the faucet stem into the hole in the faucet body. No plumber's putty is needed, since the small round rubber washers will provide the seal.

    (2) The small, flat, black rubber washer goes underneath the faucet body, then the large chrome base plate, and then the large black rubber washer.

    (3) From under the sink, slide on the thick black plastic washer first, then slide on the locknut & screw on the brass hex retaining nut. Tighten firmly into place once the faucet is properly aligned. If a small adjustment is needed from above, pad the jaws of the wrench, so as not to scratch the chrome finish

  3. Installing Optional Air-Gap Faucet:

    (1) Once the hole is prepared, assemble those parts of the faucet that belong above the sink. First, the faucet spout. Some of the faucet spouts have threads and some do not. It is not necessary to tighten the faucet spout. It is preferable to let it move freely in order to be able to move it out of the way when necessary. Insert the faucet stem into the hole in the faucet body. No plumber's putty is needed, since the small round rubber washers will provide the seal.

    (2) Slide on the chrome base plate with oblong hole underneath the faucet body and then the large black rubber washer. Slide on the white plastic spacer, open end up. Then slide on the washer & then screw on the brass hex retaining nut. Screw on brass hex nut until there is a gap between the white plastic sleeve and the base of the faucet approximately the thickness of the sink. Connect the three (3) tubes to the faucet as described in step # 6. Put the three tubes connected to faucet through sink hole and sit the faucet in place.

    (3) Under the sink, slide the steel slot washer ("C" shaped) between the white plastic spacer and the base of the sink. The open end of the slotted washer should be positioned to the same side as the connected tubes. Now tighten the brass hex nut you previously installed until faucet will not slip. Tighten firmly into place once the faucet is properly aligned. If a small adjustment is needed from above, pad the jaws of the wrench, so as not to scratch the chrome finish.

  4. Adjusting The Handle Of Standard Style Faucets, Both Air-Gap and Non Air-Gap:

    The faucet handle will need some force to pull up and lock on, this is normal. If the faucet is hard to get to lock on, taking too much force, or if it won't lock on at all, you will need to adjust the faucet handle "Tee Bar". Remove the spout and handle and adjust the Tee Bar until the faucet handle just slides on and off. Once the tee bar is adjusted slide the faucet handle back on making sure the Tee Bar stays 90 degrees with the faucet handle.

See a Typical Faucet Cut-A-Way Diagram With Parts Details

Click Here To Order New Faucets


Wrap the threads on the tank 3 or 4 times with Teflon tape (don't use any other type of pipe compounds).

Screw plastic ball valve on to the Teflon taped threads on the tank (approximately 4 to 5 full turns - do not over tighten - ball valve can crack).

Tank is pre-charged with air at 7 psi when empty. Tank can be laid on its' side if necessary (tank will hold between 2 to 3 gallons of R.O. water).

Click Here To Order Tanks

Tank Trouble Shooting Guide


It is recommended to provide generous length of tubing during installation (except drain tube). This will make future servicing and filter changing easier.

Hand tighten all fittings firmly by hand then 1 1/2 to 2 full turns with a wrench. Don't over do it and strip the plastic threads.

  1. Supply TubeSlide tube through nut on either "EASY TAP" OR "SELF PIERCING TAP"( which ever one you already installed) and then slide on plastic ferrule with the tapered end facing the seat on the fitting. Then firmly insert the tube into fitting on the feed water tap valve. Tighten firmly with a wrench. Cut the tube to length to reach the RO system. Use a razor blade to cut the tube. Be careful to make a smooth, flat, square cut. Do not crush tube. Using the above procedure, connect the other end to the water inlet (this is the first filter housing that holds the sediment pre filter). This is the connector on the side of the filter housing that does not already have a tube hooked up to it. Tighten firmly.
  2. Tank Tube Place tank and filter cartridges into their positions under the sink. Connect 1/4" tube to fitting on the end of the GAC post filter. (this fitting is a "T" fitting) Tighten firmly. Connect the other end of the tube to the tank valve. Tighten firmly.
  3. Faucet Tube Connect 1/4" tube to threaded connector on the bottom of the faucet. This is the center post of the faucet. Use supplied brass hex nut and plastic ferrule. Cut to length and connect the other end to the RO system fitting adjacent to the the tank fitting. (this fitting is a "T" fitting) This is the fitting on the post GAC filter on top of the RO system. Tighten firmly.
  4. Drain Tube - Non-Air Gap Faucet Connect 1/4" tube to the RO system drain fitting. This is the fitting on the loose line behind the RO membrane housing. Tighten firmly so tube will not pull out of fitting. There is a small cylindrical flow restrictor in this line that will help identify it. Cut tube to length and connect the other end to the drain saddle that you installed earlier. Tighten firmly.

    Drain Tube - For Optional Air Gap Faucet Connect 1/4" clear tube to 1/4" nipple on bottom of faucet. Push on firmly. The barbs on the nipple will securely hold the tube. Cut to length and connect the other end to the RO system drain fitting. This is the fitting on the loose line behind the RO membrane housing. There is a small cylindrical flow restrictor in this line that will help identify it. Tighten firmly so tube will not pull out of fitting. Connect optional 3/8" clear tube to 3/8" nipple on bottom of faucet. Push on firmly. Cut to length and connect the other end to the drain saddle that you installed earlier. Keep this tube on a down hill slope from the faucet. No dips! (Cut off excess tube if necessary)

    Check all fittings to be sure that they are all securely tightened.

    Click Here To Order Tubing


  • Turn off storage tank valve so that no water may enter tank. Turn on the cold water supply valve to the sink. Check for leaks around easy tap or self piercing valve.
  • Open R.O. faucet on sink. Open valve on easy tap or self piercing tap to turn on water to the RO system. You will hear water gurgling and filling the RO system. Water may take 10-15 minutes before dripping out faucet and at first may be black. Let water drip out of faucet for 15 full minutes and then close faucet.
  • Open ball valve on storage tank. Let tank fill for 6 to 10 hours (if you are changing filters, your tank may already be full, so you would not need to wait). Then open R.O. faucet. Drain tank completely (about 15 minutes). Shut R.O. faucet off and drain again in 6 to 10 hours.
  • Check for leaks daily for the first week and occasionally thereafter.
  • Systems With Aquatec Electric Pumps and tank level switches - PSW: Once the system start up procedures have been completed unplug the pump. Then allow the system to operate until the tank fills and the system shuts itself off. Then plug in the pump. If the pump continues to run then you must adjust the tank level pressure switch, Aquatec PSW. The PSI trigger point can be adjusted using a 050 Allen Wrench inserted into the small chrome nut in one of the two adjacent circular surfaces on the switch. Simply turn to adjust the actual water PSI shut off point for your system. Our techs love these.


  1. Install "T" on clear tube going to faucet. Run a 1/4" poly propylene tube up to 30' from the R.O. system and connect to the refrigerator. Over 30' run, use 3/8" tubing for best results. DO NOT USE COPPER. Be sure you have the recommended water pressure to your ice maker according to the refrigerator manufacturer. This tube needs tube inserts on both ends.
  2. It is recommended to install a ball valve on the tube to the refrigerator for service and start up purposes. Keep ball valve off until start up procedures are completed and R.O. tank is completely full and ready to drink. IMPORTANT: Never turn ice maker on until you have a full tank of water to avoid damaging ice makers' solenoid.

Click Here For Refrigerator Hook Up Parts


  1. Sediment Pre-Filter - Change every 3 - 6 months (more often in areas with very high turbidity in water).
  2. Carbon Pre-Filter - These filters should be changed every 6 - 12 months. This is necessary to help insure membrane life and water quality.
  3. R.O. Membrane - The R.O. membrane would be changed when rejection rate falls to 80%. The rejection rate should be tested every 6 to 12 months. The membrane can last up to 5 years depending on the water quality, the hardness of the water coming into the system and the frequency of filter changes. The only way to know when it is time to change the membrane is to know when the rejection rate of TDS falls below 75 - 80%. To do this you will need a TDS tester (total dissolved solids) This allows you to compare the amount of TDS in the incoming water vs. the drinking water. TDS testers are a basic tool in proper maintenance on any reverse osmosis system. For information on TDS testers, Click Here. For more information about TDS, Click Here.
  4. Carbon Post FilterCarbon Post Filter - This filter needs to be changed every 6 - 12 months to insure quality water. Do not wait until taste is a problem.

    Click Here For Ordering Replacement Filters For Our Systems

    Click Here For Ordering Filters For Any Other System

    All Reverse Osmosis systems require some periodic maintenance to insure you are getting the same water quality as when the system was new. There is no maintenance more important than timely filter changes. Filters need to be replaced at recommended intervals because they retain a considerable amount of debris and contaminants. Failure to change filters or use of lower quality filters, can reduce membrane life and water quality dramatically. DO NOT WAIT UNTIL YOUR WATER TASTES BAD TO REPLACE YOUR FILTERS. Remember - most contaminants don't have a foul taste except in extreme quantities.


The sediment prefilter is the first vertically mounted filter in a standard 4 stage and 5 stage RO system. The second vertical filter is a carbon prefilter. In a 5 stage system there is an additional vertical carbon prefilter. Then there is the RO membrane in a horizontally mounted housing that usually has an end cap that unscrews. The last filter is the horizontally mounted GAC carbon post filter. Some non-standard, proprietary systems vary from this configuration.
  1. Sediment And Carbon Prefilters - Turn valve to off position on easy tap or self piercing valve. Turn off storage tank ball valve. Open R.O. faucet to help de-pressurize system. Unscrew filter housings by turning counter clock wise. Remove old filters and discard. Clean filter bowls in warm soapy water. Rinse and add two table spoons of liquid household bleach and fill with water. Let stand for 5 minutes. Empty and rinse well with running tap water. Insert new filters into appropriate housings. Do not touch the filter. Use the wrapper to handle. Your hands can induce bacteria that will grow and foul the water. This is evident by "smelly" water. Replace O" rings as necessary. Be sure "O" ring is clean, lubricated and seated properly when tightening. Never use Vaseline or any other petroleum based sealant. It may breakdown the "O" ring or the seat of the filter housing and cause a failure (leak). We recommend Dow Corning 111 silicone sealant.
  2. Post Carbon Filter - Unscrew white plastic Jaco nut from both ends of post filter, or, if John Guest Quick connectors, remove clear plastic tubes. Unscrew and remove plastic fittings, if Jaco. Discard old filter. Wrap Jaco fittings with Teflon tape and re-install into new post filter. Tighten white plastic nuts to the ends of the new filter. Then approximately 1 1/2 more turns. Do Not Over Tighten. Make sure the arrow on the new filter is going with the flow of the water toward the faucet.
  3. R.O. Membrane - Turn the water off at the inlet tap valve and open the faucet. Drain the tank. Close the faucet. Close the valve on the tank. Disconnect the tube going into the end of the membrane housing on the end that has only one tube going into it. Unscrew the end cap of the membrane housing. Water will pour out. Pull out the old membrane and clean the inside of the membrane housing with warm soapy water. Membranes must remain moist at all times once wetted (installed). If the membrane is going to be reinstalled it should be put in a zip lock baggie of RO water and set into the refrigerator (not the freezer). Insert the new membrane in the direction of the arrow on the the membrane. The end with the two small "O" rings goes in first on the regular, industry standard membranes. The end with the large rubber ring (brine seal) goes in last, next to the removable end cap. Be sure that the center tube of the membrane is seating into the receiver in the bottom of the housing. Push firmly! Screw the end cap back on and reconnect the tube to the membrane housing. Open the faucet. Open the inlet feed water tap valve. Do not open the tank valve. Allow the water to drip from the faucet for 1 hour. This will fulfill the requirement of flushing the membrane as may be described on the membrane packaging. After one hour, close the faucet and open the tank valve. Allow the system to fill the tank and shut off. Then open the faucet and drain the tank.Repeat this 2 more times, for a total of 3 full tanks to fill and then drain. This will flush the preservative from the membrane prior to drinking and any black, dirt looking, carbon fines from the GAC post filter.
  4. Check the air pressure in the tank each time that you change filters. It is very important that the air pressure is correct. For more on this see: TANK AIR PRESSURE

Step 11 - RECOMMENDED SANITIZING PROCEDURE (normal process time is about an hour)

The best time to sanitize is when changing all the filters and/or when changing the membrane. It is recommended to sanitize all water filter and R.O. systems a minimum of once a year. You can skip this step on a new system. It is for filter changes only.

  1. Fill a large pitcher with pure water from the system. Shut off the water inlet tap valve. Drain the rest of the water out of R.O. tank by opening the faucet. Remove the old prefilters. Remove the RO membrane even if not replacing it. Place the membrane in the pitcher of RO water. Reassemble the membrane housing without the membrane inside. Place one packet of Pro Products Sani-System sanitizer in the first filter housing and reinstall the housings onto the system.

    In the past systems were sanitized using bleach. This is caustic to the RO system parts and can cause a system to fail sooner than expected. Protect your system by using Pro Products Sani-System sanitizer. You won't have to worry anymore about performing enough flushes to rinse all of the bleach out of the system before drinking. We highly recommend the use of the Pro Products Sani-System sanitizer. It is EPA approved and is the best sanitizer available anywhere. And it takes only one minute to work.

  2. Turn water supply back on to about 30% of maximum flow rate and let storage tank slowly fill with tap water (approximately 5 minutes). Open the faucet to allow air to bleed off. Close the faucet once water starts to flow from it in a full, steady stream.
  3. Shut off the incoming water supply once the tank is full. Let entire system sit one minute to thoroughly sanitize in Pro Products Sani-System sanitizer. (better than the old process of waiting for about 30 minutes with a bleach solution and then 4 or 5 flush cycles).
  4. Open faucet and let the storage tank drain until empty. Shut off faucet when empty. Turn on inlet water at easy tap or self piercing tap valve. Allow tank to fill with water. Again, turn off the incoming tap valve and drain the tank. Do this 1 time to completely flush the Pro Products Sani-System sanitizer from the system. Then turn off the incoming tap valve and install the new filters and membrane. This is when you will change the post filter also. Then follow normal system start up procedures.

Do not touch the filter cartridges with your fingers. Use the wrapper to handle them. Your hands can induce bacteria that will grow and foul the water. This is evident by "smelly" water.