Owner`s manual

Fig.6

Calibration - Model 250

Model 250 is equipped with a pressure switch located at the top of the motor unit just behind

the air outlet. The pressure switch controls the chemical pump by switching the pump on only if

there is sufficient air pressure on the air manifold. The unit is shipped with the wire tab attached to

the Normally OPEN connection at the pressure switch.

Temporarily move the wire tab to the Normally CLOSED connection. This will allow you to calibrate

the pump independently of other parts of the system. It is not necessary to operate the inverter or

blower to calibrate the pump.

Now loosen the knurled knobs slightly on each side of the pointer of the pump so that the pointer

can be adjusted. Turn the black knob counterclockwise to increase flow. Measure flow rate as

above. When the desired flow rate is achieved, tighten knurled nuts and reconnect chemical line to

nozzles. IMPORTANT Reset pressure switch wire to the NORMALLY OPEN connection tab.

Normally

CLOSED

Normally

OPEN

COMMON

Fig.5