Culligan M1 Series Installation, Operation And Service Instructions page 28

6. When the one-minute period has elapsed, the controller checks to see if there is sufficient incoming water pres-
sure to operate the RO.
a. If there IS pressure, the controller turns on the main pump and the RO produces permeate water. The
PUMP ON LED is lighted.
b. If there is NOT sufficient pressure, the entire process starts over, beginning with the one-hour delay.
c. As long as there is applied power and water pressure is being supplied to the unit, the RO will repeat
this delay, flush, and attempt to start cycle indefinitely up to 24 restart attempts per day.
7. Once the controller successfully enters the make-water mode, the first four LEDs will be lighted: red, green,
green, and green. The pump will continue to operate and produce RO water until one of the following five
events occurs:
• Tank Full switch is OPEN
• Pretreatment lockout switch is OPEN
• Loss of electrical power
• Loss of inlet pressure
• Two-hour continuous make-water timer expiration
When any of these five events occurs the system immediately ceases making RO water. The pump will turn off,
and the inlet solenoid will close.
8. If the unit has stopped for either tank full or pretreatment lockout conditions, it will remain off until these condi-
tions no longer exist, and the LED indicating POWER status will be lighted. Once the tank is full or the pretreat-
ment lockout condition ends, the LED indicating READY is lighted and the unit will then reopen the inlet sole-
noid. Wait one minute, and then start the pump to return to the make-water condition.
9. If the unit has stopped because of either an electrical power loss or loss of inlet pressure, the system will follow
the behavior described in step 1.
10. If the unit stops because it has been in a continuous make-water operation for the previous two hours, the pump
will remain off for one minute. During this time, the inlet solenoid valve will remain open, and the system will
perform a line-pressure front-side membrane flush to drain. The first three LEDs will be lighted. At the end of the
minute, the system will return to make-water mode. The fourth LED will now be lighted again.
If the system includes an optional TDS probe, and the measured product TDS rises above the customer-set threshold for
at least three minutes, then the product quality is too low. The system will shut off the pump (to stop making water) and
close the inlet valve. The LEDs for POWER, READY, and HIGH TDS will be lighted.
Setting the TDS Threshold
There is a bank of DIP switches located along the left side of the CP Plus controller. See Figure 18 on page 20. Each
switch can be set to either ON or OFF. The system continuously monitors the product water TDS while it is making RO
water. If the product TDS falls below the specified threshold for more than three minutes, the system will stop making RO
water. The threshold specifications is selected as shown below:
Dip Switch 1 Dip Switch 2
ON OFF
OFF ON
OFF OFF
OFF OFF
OFF OFF
NOTE DIP switch settings are not designed to perform accurately when multiple DIP switches are in the
ON position. Setting more than one switch to the ON position will result in a reading less than either
switch setting.
24 Culligan® M1 Series Reverse Osmosis
Dip Switch 3 Dip Switch 4
OFF OFF
OFF OFF
ON OFF
OFF ON
OFF OFF
Dip Switch 5 Product Water TDS
Approximate
Threshold
OFF 25 ppm max TDS
OFF 50 ppm max TDS
OFF 75 ppm max TDS
OFF 100 ppm max TDS
ON 125 ppm max TDS
24 Cat. No. 01022940