DEMA 633AG-1 & 633AG-4 BLEND CENTER
INSTALLATION INSTRUCTIONS
I-459
Pg. 4 of 6
Rev. F-42084
9/8/16
4.
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.
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 up & down 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 holes) 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 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.
