DEMA SINGLE-FEED
MODEL: 651GAP, 651GAP-1 & 651GAP-1M
INSTALLATION INSTRUCTIONS
I-781
Pg. 3 of 6
Rev. G-42173 10/04/16
III. OPERATION:
The model 651GAP is activated by turning the on-off ball valve fully counterclockwise. When the desired amount of chemical
water solution has been obtained turn the ball valve fully clockwise.
Note: Do not use ball valve to throttle chemical water
flow rate; this will result in inconsistent induction rates.
IV. SERVICING:
Caution: Turn off water supply before servicing.
A.
Proportioner fails to draw chemical:
1. Pinch outlet tube to create back pressure, which will cause unit to prime. The foot valve will keep the inlet tube primed
thereafter.
2. Insufficient water supply pressure. 20 PSI is the minimum allowable.
B.
Proportioner stops drawing chemical:
1.
Inspect foot valve for dried chemical or dirt. Soak in hot water to clean.
2.
Proportioner metering tip clogged with dried chemical. Remove tip and try injecting in hot water. If there is no suction,
remove proportioner and soak in hot water to clear interior passages.
3.
Inspect proportioner to ensure that there are no mineral deposit build-ups on the nozzle. If so, soak proportioner body in
deliming solution. (Remove all parts attached to proportioner before soaking in deliming solution.)
Note: Use care
when handling hazardous chemicals.
C.
Proportioner continues to draw chemical after water valve closes:
Chemical supply is higher than bottom of discharge tube creating a natural siphon. Lower the supply vessel or hang up
outlet tube after use.
D.
Valve Malfunction:
Check that the button moves freely in & out and that a "click" can be heard when the button is pushed and released,
indicating that the magnet is activating the plunger properly. Remove cover. To inspect internal parts, unscrew magnet
housing and carefully pull off the enclosing tube so as not to drop the plunger, kick-off spring, and spacer. Check for
dirt or damage impending plunger and kick-off spring movement. Inspect the diaphragm, making sure the two small pin
holes (bleed hole) in the diaphragm convolution are clear to allow the valve to close.
Caution: When servicing unit, be sure that replacement parts have been installed according to the drawing.
RETURNS:
NO MERCHANDISE MAY BE RETURNED FOR CREDIT WITHOUT DEMA’S WRITTEN PERMISSION.
RETURN MERCHANDISE AUTHORIZATION NUMBER REQUIRED IN ADVANCE OF RETURN.
WARRANTY:
DEMA products are warranted against defective material and workmanship under normal use and service for one year
from the date of manufacture. This limited warranty does not apply to any products, which have a normal life
shorter than one year or failure and damage caused by chemicals, corrosion, improper voltage supply, physical
abuse, or misapplication. Rubber and synthetic rubber parts such as “O”- rings, diaphragms, squeeze tubing
and gaskets are considered expendable and are not covered under warranty. This warranty is extended only to
the original buyer of DEMA products. If products are altered or repaired without prior approval of DEMA, this
warranty will be void.
Defective units or parts should be returned to the factory with transportation prepaid. If inspection shows them
to be defective, they will be repaired or replaced without charge, F.O.B. factory. DEMA assumes no liability
for damages. Return merchandise authorization number, to return units for repair or replacement, must be
granted in advance of return.
