Weil-McLain UO-3 CV, Instruction Manual

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fi ring, the control shuts down the burner, enters
a 60 second recycle delay, and then repeats the
above ignition sequence. If
fl ame is lost three times
in a row, the control locks out to prevent cycling
with repetitious
fl ame loss due to poor combustion.
BURNER MOTOR-OFF DELAY.
The fuel valve
is closed and the burner motor is kept on for the
selected motor-off delay time before the control
returns the burner to standby.
8.
Figure 9. Typical Burner Wiring & Burner Sequence of Operation for R7184P Control.
Refer to the appliance manufacturer’s wiring diagram for actual specifi cations.
STANDBY.
The burner is idle, waiting for a call for
heat. When a call for heat is initiated, there is a 3-10
second delay while the control performs a safe start
check.
VALVE-ON DELAY.
The ignition and motor are turned
on for a 15 second valve-on delay.
TRIAL FOR IGNITION (TFI).
The fuel valve is
opened. A fl ame should be established within the 15
second lockout time.
LOCKOUT.
If fl ame is not sensed by the end of the
TFI, the control shuts down on safety lockout and
must be manually reset. If the control locks out three
times in a row, the control enters restricted lockout.
IGNITION CARRYOVER.
Once fl ame is established,
the ignition remains on for 10 seconds to ensure fl ame
stability before turning off. If the control is wired for
intermittent duty ignition, the ignition unit stays on the
entire time the motor is running.
RUN.
The burner runs until the call for heat is sati fi ed.
The burner is then sent to burner motor off delay, if
applicable, or it is shut down and sent to standby.
RECYCLE.
If the fl ame is lost while the burner is
1.
2.
3.
4.
5.
6.
7.
Feature Interrupted
ignition
Limited reset,
Limited recycle
Diagnostic LED,
cad cell indicator
Valve-on
delay
Burner motor
off delay
Alarm
Contacts
R7184A YES YES YES — — —
R7184B YES YES YES YES — —
R7184P YES YES YES YES YES Optional
Control System Features
SK9359
61351
Section: Burner Control