23
M720 pH/ORP Controller Owner’s Manual
C. Maintenance
1. Winterizing (extended shutdowns or colder climates)
a. Turn o the M720 controller and shut o main power to
controller.
b. Gently remove the ph and ORP sensors from the ow
cell. Fill the provided protecve caps (removed during
installaon) with water and re-install onto each sensor, and
store in a warm, secure locaon.
c. Drain the water from the ow cell.
2. Cleaning the sensor ps
Note: It is important to keep the sensor ps clean in order to
ensure accurate readings.
a. Sensor ps should be cleaned every 1 to 3 months for
commercial pools and spas, and every 3 to 6 months
for residenal pools and spas. Determine the necessary
frequency by comparing the readings before and aer the
cleaning. Idencal readings mean that the cleaning me
can be extended.
b. Turn o the M720 controller.
c. Close the right and le valves at the boom of the ow
cell.
d. Loosen the nut ng on the sensor and gently remove it
from the ow cell.
e. Swirl the sensor p for 5 seconds in Muriac acid or white
vinegar and rinse with water. Note: Do not touch or brush
the sensor p.
f. For commercial pools and spas: For every 3rd cleaning,
swirl the sensor p in a liquid soap and water soluon.
Rinse with water.
g. Gently re-insert the sensor into the ow cell and hand
ghten the nut ng.