8
OM-AH/1E (CE) INTERNATIONAL
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 thermostat, 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 thermostat
switch opens. This stops the signal to the gas control valve and shuts off
gas to the main burner. The pilot flame stays lit.
4. When the kettle cools below the set temperature, the thermostat switch
closes and start 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. High limit pressure switch, set to open at about 26 PSI and to shut down the
burners until jacket pressure is decreased.
3. Pressure relief safety valve, which will release steam if jacket pressure
exceeds 30 PSI.
4. 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
Kettle continues
heating after
it reaches
the desired
temperature.
User
a. Thermostat dial setting.
Auth Service
Rep Only
b. Thermostat calibration. X
c. Thermostat operation. The thermostat should click when
the dial is rotated above and below the setting for the
temperature of the kettle. X
Kettle stops
heating before
it reaches
the desired
temperature.
User
a. Thermostat dial setting.
Auth Service
Rep Only
b. Thermostat calibration. X
c. Thermostat operation. Thermostat should click when
the dial is rotated above and below the setting for the
temperature of the kettle. X
Safety valve
pops open.
User
a. For air in the jacket. See “Jacket Vacuum” in the
Maintenance section.
b. Thermostat dial setting.
Auth Service
Rep Only
c. For defective thermostat. The thermostat 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 29 PSI, replace. X
Burners will not
light.
User
a. That the main gas supply valve is open. (handle is in line
with the gas pipe).
b. Gas supply to the building.
Auth Service
Rep Only
c. Thermostat operation. The thermostat should click when the
dial is rotated to settings above and below the temperature
of the kettle. X
System does
not produce a
spark.
Auth Service
Rep Only
a. AC voltage between terminals on secondary side of
transformer with unit power turned on. 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 burner ceramic insulator for crack or break. X
d. Pilot spark gap. Regap. 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 b). 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
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 b).
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
