Form RGM 433-CV/LN, Mfg No. 177854 (Revision 1), Page 13
Figure 7 - Electrical Connections, DIP Switch Settings,
and LED Signal Codes on the Integrated Circuit Board
in the Control Compartment
Circuit Board LED Flash Codes
Slow Flash ..... Normal Operation, No Call for Heat
Fast Flash ...... Normal Operation, Call for Heat
2 Flashes ........ System Lockout, Failed to Detect or Sustain Flame
3 Flashes ......... Pressure Switch Open or Closed
4 Flashes ......... High Limit or Flame Rollout Switch Open
5 Flashes ......... Flame Sensed and Gas Valve Not Energized
Steady On ....... Internal Failure - Replace the Circuit Board
DIP Switch Settings
SW1
Fan Delay
1
2
to Off
OFF
OFF
90 seconds
OFF* ON*
120 seconds*
ON
OFF
180 seconds
ON
ON
240 seconds
*Standard factory setting.
DANGER: Safe operation of this unit requires
proper venting flow. NEVER bypass combustion
air proving switch or attempt to operate the unit
without the venter running and the proper flow
in the vent system. Hazardous conditions could
result. See Hazard Levels, page 1.
16. Gas Valve
The main operating gas valve is powered by the 24-volt control circuit
through the thermostat and safety controls. The main control valve is
of the diaphragm type providing regulated gas flow preset at the fac-
tory.
WARNING: The operating valve is the prime
safety shutoff. All gas supply lines must be free
of dirt or scale before connecting the unit to
ensure positive closure. See Hazard Levels, page
1.
17. Ignition System
This heater is equipped with a direct spark integrated control system.
The system monitors the safety devices and controls the operation of
the fan and venter motors and the gas valve between heat cycles.
Ignition System Operating Sequence -- On a call for heat from the
thermostat, the system energizes the venter motor and goes through a
10-second prepurge. The system verifies that both the pressure switch
and the high limit are in the closed state. The gas valve is then ener-
gized and the ignition system provides the high voltage spark to the
electrode to ignite the main burner gas. Burner flame is electronically
sensed by the control upon carryover of all burners. (A separate solid
metal probe is used as the flame sensing function. A low voltage elec-
trical signal is imposed on the metal probe which is electrically iso-
lated from ground. When the flame impinges on the flame sensing probe,
the flame acts as a conduction path to ground. The flame rectifies and
completes the DC circuit, and the ignition system acknowledges the
flame.) The fan motor is energized by the system after 30 seconds of
flame sensing.
After the thermostat has been satisfied, the system de-energizes the gas
valve, the venter motor goes through a 45-second post-purge, and the
fan motor remains energized for an additional 180 seconds.
NOTE: This is a three trial system, should the unit not sense burner
flame, the unit will lockout for one hour before initiating another trial
for ignition. To initiate another trial for ignition before the one hour,
requires that either the thermostat be reset or the power to the unit be
interrupted for 30 seconds.
Ignitor
Connection
Line Voltage
Connection
24-volt Terminal Strip for
Thermostat Connections
(refer to wiring diagram)
DIP Switch for Regulating
Fan Off Delay Time
Model
S tart-Up
Cold
Equilibrium
S et
Point
"OFF"
S et
Point
"ON"
FT30-CV
-0.43
-0.20
-0.15
-0.20
FT45-CV or LN
-0.43
-0.205
-0.15
-0.20
CAUTION: Route the wires so that they do not
contact the flue wrapper or venter housing.
Consult the wiring diagram supplied with your heater. Typical wiring
diagram is on page 14.
CAUTION: If any of the original wire as supplied
with the appliance must be replaced, it must be
replaced with wiring material having a temperature
rating of at least 105°C, except for limit control and
sensor lead wires which must be 150°C. See Hazard
Levels, page 1.
Thermostat and Connections
A thermostat is not standard equipment but is an installation require-
ment. Use either an optional thermostat available with the heater or a
field-supplied 24-volt thermostat. Install according to the thermostat
manufacturer's instructions, paying particular attention to the require-
ments regarding the location of the thermostat.
Make sure that the heat anticipator setting on the thermostat is 0.6
amps (or in accordance with the amperage value noted on the wiring
diagram of your heater).
14. Fan Motor
The fan motor is equipped with thermal overload protection of the
automatic reset type. Should the motor refuse to run, it may be because
of improper current characteristics. Make certain that the correct volt-
age is available at the motor.
15. Combustion Air Proving
Switch
The combustion air proving switch is a pressure sensitive switch that
monitors air pressure to ensure that proper combustion air flow is avail-
able. The switch is a single pole - normally open - device which closes
when a decreasing pressure is sensed in the venter housing.
On start-up when the heater is cold, the sensing pressure is at the most
negative level, and as the heater and flue system warm up, the sensing
pressure becomes less negative. After the system has reached equilib-
rium (about 20 minutes), the sensing pressure levels off.
If a restriction or excessive flue length or turns cause the sensing pres-
sure to be outside the switch setpoint, the pressure switch will function
to shut off the main burners. The main burners will remain off until the
system has cooled and/or the flue system resistance is reduced. The
Table below lists the approximate water column negative pressure read-
ings and switch setpoints for sea level operating conditions.
