Cuno SQC Series User Manual

When to Replace the RO Membrane Cartridge
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As determined by a built-in percent rejection (PR) monitor:  
The monitor is factory preset so that a green light will be 
displayed when the water quality is good, and a red or 
yellow light indicates that cartridge replacement may be 
necessary.  If a red or yellow light is displayed, the faucet 
should be opened and the storage tank trained.  After it 
has refilled, check the water quality again.  If a red or 
yellow light is still displayed, the membrane should be 
replaced.

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If a PR monitor is not used, your dealer or supplier will 
offer a bi-annual testing service.

Close the feed water tapping valve.  Lift up on the faucet 
handle to drain the tank.  Wait five (5) minutes for the 
purification assembly to completely depressurize.

Make sure that there is some slack in the red SFC tubing 
connected to the fitting at the bottom of the RO membrane 
cartridge.  Twist the cartridge 1/4 turn clockwise so that 
the tubing connection is accessible.  (See Fig. 8)

Remove the red SFC tubing by depressing the small gray 
collet and pulling the tubing away from the fitting.

Note: It is advisable to check the end of the red SFC tubing
for nicks or scratches.  If any are observed, cut off 1/4" from
the end of the tubing with a sharp razor knife.

Firmly pull the cartridge away from the head.  (It may be 
necessary to twist the cartridge slightly from side to side.)

Remove the new RO membrane cartridge from its sanitary 
sealed wrapper.  (Double check to see that it is the correct 
replacement by comparing the labels.)  Rinse it with tap 
water and dry it off.

Remove the white plug from the fitting at the bottom of the 
cartridge by pushing in the small gray collet and pulling out 
the plug.

Remove the red plastic cap from the top of the cartridge.

Using tap water, food grade silicone lubricant or glycerin, 
wet the O-ring seals to make cartridge insertion easier.

Reconnect the red SFC reject tubing by inserting it into the 
fitting at the bottom of the new RO membrane cartridge as far 
as it will go.  Line up the cartridge ears, insert the cartridge 
and push it into the head until it is fully seated.  Twist the 
cartridge 1/4 turn counterclockwise to lock it into place.

10) Open the feed water tapping valve and carefully check for 

leaks.  Carefully inspect the fitting at the bottom of the new 
RO membrane cartridge.

11) Follow the sanitizing procedure for the storage tank and 

the purification assembly outlined below.

To assure the highest quality water from your Water Factory
Systems RO Drinking Water Appliance, it is important to routine-
ly sanitize both the storage tank and the purification assembly.

Upon start-up as described in the beginning of this manual.

After any servicing or routine maintenance which involves 
the RO membrane cartridge, postfilter cartridge(s), storage 
tank, or faucet.

After any servicing or routine maintenance which involves 
the prefilter cartridge or the RO membrane cartridge.  

After any extended period of non-use (over 30 days) unless 
the cartridges are stored inside a sealed plastic bag in the 
refrigerator.

How to Sanitize the Storage Tank 
Sanitizing the storage tank generally requires:
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The Water Factory Tank Sanitizing Unit (P/N 50-011) or an 
equivalent device such as an empty filter housing with 
fittings and tubing.

Common household bleach (5.25% non-scented).

A measuring spoon or a 0-10 ml graduated cylinder.

Fig. 8

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