4.5.4
Re-circulation Valve
The manual control valve (P/N 7400-1.) in its OFF position directs flow to a by-pass valve (P/N 7400) which may
be positioned to re-circulate fluid back to the tank or return the fluid to the pump inlet line. For herbicide applications or
other high volume uses, the by-pass valve handle shall be rotated clockwise to direct flow back to the tank. If excessive
agent foaming occurs, it is recommended that the valve handle be rotated counter clockwise to direct the fluid into the
pump intake line.
4.5.5
Decontamination
BLUE and WHITE are soluble in water and flushing the system with 30 gallons of water should leave the system
relatively clean. Traces of WHITE are most difficult to remove and probably will be found in the system for some time
after repeated spraying has been done with other materials. WHITE has a relatively long residual activity in soil and the
area to rinse the system should be chosen with attention to minimizing damage to desirable vegetation in the area.
BLUE is relatively rapidly rendered inactive in the soil. BLUE contains a detergent which may assist in flushing out
residues of the chemical.
ORANGE is soluble in many organic solvents and #2 diesel fuel has been commonly used to remove this
material from spray systems and from accessory gear.
None of these three chemicals should be allowed to stand in the system It is advisable to clean the system out
directly after spraying using the appropriate solvent and finish with #2 diesel fuel as the last rinse. The check valves
(P/N 4623 ASB) should be removed, cleaned and dried.
The check valve diaphragms should be inspected fur
replacement as necessary where evidence of deterioration is found.
29e
