18 OM-DHS
WARNING
TO AVOID INJURY, READ AND FOLLOW ALL
PRECAUTIONS ON THE LABEL OF THE
WATER TREATMENT COMPOUND.
Maintenance
4. Water Treatment Procedure
a. Obtain water treatment compound and a pH test kit from your Groen
Service Agent.
b. Fill a mixing container with the measured amount of water required. Dis-
tilled water is recommended. DHS-40, DHS/T-40 = 4 Gallon approximate
jacket capacity.
c. Hang a strip of pH test paper on the rim of the container, with about 1
inch of the strip below the surface of the water.
d. Measure the water treatment compound. One way to do this is to add the
compound from a measuring cup.
e. Stir the water continuously, while you slowly add treatment compound,
until the water has a pH between 10.5 and 11.5. Judge the pH by fre-
quently comparing the test strip color with the color chart provided in
the test kit. Caution: Do not add excess amount of treatment compound.
Excess amount could cause extensive corrosion.
f. As you add water to the jacket, check water level to ensure that it is in
the middle of the sight glass.
g. Record the exact amounts of water and treatment compound needed.
These amounts may be used again, if the same water sources and com-
pound are used. However, it is best to check the pH each time treated
water is prepared.
5. Component Replacement
When component replacement involves breaking a gas pipe connection, check
the new connection with soap solution or an appropriate leak detector. DO NOT
USE A FLAME TO TEST FOR LEAKS.
Internal wiring is marked as shown on the circuit schematic drawings (inside
control housing and in this manual). Be sure that new components are wired in
the same manner as old components. An examination of the circuit schematic
shows that the safety components are wired in series. In most cases, a faulty
component may be isolated with a jumper wire to verify that the component is
faulty. If this determination is made, contact a certified Groen Service Agency
for assistance.
WARNING
BEFORE REPLACING ANY PARTS,
DISCONNECT THE UNIT FROM THE ELECTRIC
POWER SUPPLY AND CLOSE THE MAIN GAS
VALVE. ALLOW 5 MINUTES FOR
UNBURNED GAS TO VENT.
