8
OM-TDH(C)-20/24/40/48 (C,A) (CE) INTERNATIONAL
3. 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.
4. Measure the water treatment compound. One way to do this is to add the
compound from a measuring cup.
5. 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 frequently
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.
7. Record the exact amounts of water and treatment compound needed. These
amounts may be used again, if the same water sources and compound are
used. However, it is best to check the pH each time treated water is prepared.
SEQUENCE OF OPERATION
The following “action-reaction” outline is provided to help understand how the
kettle works.
1. When the power switch is turned on, it starts the spark igniter and opens the
automatic valve for the pilot burner. The spark ignites a pilot flame, which
heats the sensor. The sensor then sends a signal to turn off the spark. The
flame thereafter acts as a standing pilot until the power is turned off.
2. If the pilot flame is not sensed within 90 seconds after spark begins, a timer
shuts down the entire operation. To attempt a second trial for ignition, turn
off the power switch. Check the gas supply valves and wait five minutes
before trying again by switching power on. If you cannot establish a pilot
flame in four tries, close all valves, turn off the power, and contact an
authorized Service Agency.
3. When the operator sets a temperature on the controller, it causes the
automatic valve to admit gas to the main burner, where it is ignited by the
pilot flame. When the kettle reaches the set temperature, the relay switch
opens. This stops the signal to the gas control valve and shuts off gas to the
main burner. The pilot flame remains lit. When the kettle cools below the set
temperature, the relay switch closes and starts another cycle. On and off
cycling continues and maintains the kettle at the desired temperature. This
action is indicated by the Heat indicator light.
The kettle has the following safety features in addition to the 90-second ignition timer:
1. Low water cutoff relay that will shut off gas supplies to all burners until the
jacket water level is corrected.
2. Pressure switch, set to open at about 46 PSI (345 kPa, 3.17 bars) and to shut
down the burners until jacket pressure is decreased.
3. Pop safety valve, which will release steam if jacket pressure exceeds 50 PSI
(345 kPa, 3.45 bars).
4. Tilt switch, which shuts off all burners when the kettle is tilted.
5. Gas pressure regulator built into the gas control valve.
REPLACEMENT PARTS
To order parts, contact your Authorized Service Agent. Supply the model
designation, serial number, part description, part number, quantity, and when
applicable, voltage and phase.
CONTACT US
If you have questions pertaining to the content in this manual, contact Unified
Brands at 888-994-7636.
TROUBLESHOOTING
This unit is designed to operate smoothly and efficiently if properly maintained.
However, the following is a list of checks to make in the event of a problem.
Wiring diagrams are found at the end of this manual. When in doubt, turn unit
off and call for service at 888-994-7636. If an item on the check list is marked
with (X), it means that the work should be done by an Authorized Service Agent.
SYMPTOM
WHO
WHAT TO CHECK
X indicates items which must be performed by authorized technician.
Display not lit
(Advanced & C2T only)
User
a. That power supply is on.
Auth Service
Rep Only
b. Fuses, accessible by removing caps on the side of the control box.
c. For loose or broken wires. X
d. Temperature controller functioning, by listening for a click
when the switch opens or closes and verifying LEDs on back
of board. X
e. Contactor functioning. X
PROB in display
(Advanced & C2T only)
Auth Service
Rep Only
a. For loose or broken wires or damaged/failed RTD probe. X
b. PCB board malfunction/failure
HI in display
(Advanced & C2T only)
Auth Service
Rep Only
a. For loose or broken wires or damaged/failed RTD probe. X
b. PCB board malfunction/failure
Kettle is hard to tilt
User
a. Gears for foreign materials, and lubrication.
Auth Service
Rep Only
b. Gears for alignment. X
c. Worm gears or broken gears. X
Kettle continues
heating after it
reaches the
desired temperature
User
a. Temperature Controller dial setting.
Auth Service
Rep Only
b. Temperature Controller calibration and offset.X
c. Temperature Controller operation. The Temperature Controller
should click when the dial is rotated to settings above and
below the temperature of the kettle.X
Kettle stops heating
before it reaches the
desired temperature
User
a. Temperature Controller dial setting.
Auth Service
Rep Only
b. Temperature Controller calibration and offset.X
c. Temperature Controller operation. The Temperature Controller
should click when the dial is rotated to settings above and
below the temperature of the kettle.X
Safety Valve pops
open
User
a. For air in the jacket. See “Jacket Vacuum” in the Maintenance
b. Temperature Controller dial setting.
Auth Service
Rep Only
c. For defective Temperature Controller. The relay should click
when the dial is rotated to settings above and below the
temperature of the kettle. If defective, replace.X
d. For defective safety valve. If the valve pops at pressures below
49 PSI, replace.X
Burners will not light
User
a. That the main gas supply valve is open. (handle is in line with
gas pipe).
b. Gas supply to the building.
c. That the kettle body is not tilted.
Auth Service
Rep Only
d. Temperature Controller operation. The relay should click
when the dial is rotated to settings above and below the
temperature of the kettle.X
e. That tilt limit switch is closed when body is not tilted.X
System does not
produce a
spark
Auth Service
Rep Only
a. AC voltage between terminals on secondary side of
transformer. If it is not 24 Volt, replace the transformer. X
b. That the high tension cable is firmly attached and in good
condition. If cracked or brittle, replace.X
c. Pilot electric ceramic for crack or break.X
d. Pilot spark gap. Regap.X
Spark is present
but the pilot will
not light
Auth Service
Rep Only
a. That the pilot valve is securely connected to terminals. X
b. For 24 VAC at terminals PV and PV/MV. If 24V is not present,
replace the ignition control module. X
b. That gas pressure is at least 3.5” W.C. (8.7818 ub).
c. For gas at the pilot. If it is not flowing:
(1) Check the pilot gas line for kinks and obstructions. X
(2) Clean orifice, if necessary. X
(3) Check magnetic operator for pilot valve on gas valve.
Repair or replace as necessary. X
d. That the pilot spark gap is located in the pilot gas stream. If
not, adjust or replace the pilot burner. X
e. For drafts. Shield the pilot burner, if necessary. X
Pilot lights, but
main burner will
not come on and
spark does not
stay on
Auth Service
Rep Only
a. For 24 V between terminals MV and PV/MV while pilot is burning.
If 24V is not present, replace the ignition control module. X
b. That gas pressure is at least 3.5” W.C.(8.7818 ub). X
c. Electrical connections of the main valve to terminals, to
assure that they are securely attached. Check magnetic
operator for main valve on gas valve. Repair or replace
as necessary. X
Pilot lights, but
main burner will
not come on, the
spark stays on
Auth Service
Rep Only
a. Check for bad burner ground. If necessary, repair with
high temperature wire. X
b. Pilot burner ceramic insulator for cracks. X
c. That cable is not grounded out. If it is, correct the
ground-out condition or replace cable. X
d. For proper gas pressure. X
e. Clean pilot assembly, or replace if necessary. X
f. Tighten all mechanical and electrical connections. X
g. If the pilot flame is weak, increase pilot orifice size. X
h. Replace ignition control module. X
Main burner
comes on but will
not stay on
Auth Service
Rep Only
a. Check burner ground for bad wire or connection. Replace
if necessary with high temperature wire. X
b. Check for low gas supply pressure. If necessary, replace
ignition control module. X
