Installation / Operation Instruction Manual
Table Of Contents
- WITH TROUBLESHOOTING GUIDE
- Non-Flue Damper Models (Figure 2)
- Flue Damper Models and Non-Flue Damper Models (Figure 3)
- Non-Flue Damper Models (Figure 4)
- Front, sides and Rear “A”
- Input
- 2 in. (5.1 CM)
- Less than or equal to 300,000 BTUH
- 6 in (15.2 CM)
- Greater than 300,000 BTUH
- IMPORTANT-The flow of combustion and ventilating air must not be obstructed.
- MECHANICAL EXHAUSTING OF ROOM AIR - Where an exhaust fan is installed in the same room with this water heater and combustion air is drawn from inside the room, sufficient openings for air must be provided in the walls. UNDERSIZED OPENINGS WILL CAUSE A...
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SECTION XI: DIAGNOSTIC AND TROUBLESHOOTING GUIDE
OPERATING AND TROUBLESHOOTING GUIDE-SEQUENCE OF OPERATION (STANDING PILOT WITH
MILLI-VOLT CONTROL)
1. With the pilot lit, the pilot burner assembly power pile generates milli-voltage to energize the magnet coil in the gas
valve permitting gas flow through pilot and to the main gas ports of the valve. Simultaneously, milli-voltage is also
directed to the ECO (energy cut off) switches located in the thermostat.
2. Set the control knob on the gas valve to “ON” position.
3. Set the adjustable thermostat to desired water temperature.
4. As the water temperature decreases below the thermostat setting in the tank, the contacts in the thermostat will
close, thereby energizing the circuit to the main valve permitting the flow of gas to the main burner.
5. A slow opening feature of the gas valve will cause the burners to light slowly at a reduced manifold pressure. After a
few seconds (allowing the combustion system to stabilize), the manifold pressure will increase to the maximum
setting of the gas valve.
6. The burners will continue to fire until the thermostat becomes satisfied, where upon the contacts will open, de-
energize the main valve circuit, and the burners will extinguish.
7. If the temperature rises above fixed ECO (energy cut off) setting, the ECO contacts will open simultaneously de-
energizing pilot and main valve circuits, and the burners will be extinguished.
DIAGNOSTIC GUIDE FOR HONEYWELL INTEGRATED CONTROL SYSTEM FOR FLUE DAMPER
MODELS-SEQUENCE OF OPERATION
1. When the tank temperature drops below the temperature setpoint on the display, the control opens the flue damper
to start the ignition sequence.
2. When the flue damper reaches the full open position, the end switch in the damper closes, completing the 24 volt
circuit to the control.
3. After the end switch closes, the control sends 24 volt power to the pilot valve “PV” terminals on the gas valve
allowing pilot gas to flow to the pilot. The control also sends high voltage through the pilot electrode to spark to the
pilot hood and ignite the pilot gas. If the pilot does not ignite within 90 seconds, the pilot valve is denergized and the
sparking stops for 65 seconds, and will attempt to ignite the pilot two more times. If the pilot does not light on the 3
rd
attempt, the control will go into “soft lockout” for 1 hour and then will repeat the 3 ignition attempts.
4. When the pilot is lit, the flame is sensed by the flame sense rod. The flame sense signal received by the control
board causes the sparking to stop and the main gas valve to open. The main burners ignite from the pilot flame. The
pilot is continually monitored by the flame sensing circuit. If for any reason, the pilot flame is not sensed by the flame
sensing circuit, the gas valves close. After a 65 second delay, the pilot valve opens and the pilot electrode sparks to
relight the pilot. The same sequence will occur in the event of a power supply or gas supply interruption.
5. The main burners continue to operate until the water temperature in the tank increases past the control setpoint,
which will cause the gas valve to close. The flue damper closes shortly after the gas valve closes. The water heater
remains in the standby mode until the temperature drops below the setpoint and initiates another heating cycle.
6. If for some reason, the tank temperature should reach or exceed 200˚F, then the control closes the gas valve and
goes into a “hard lockout” state and will not operate until reset by a qualified service person. The display will read
“error code 65”, which indicates the tank high limit temperature has been exceeded. No attempt should be made to
reset the control until a service person has corrected the cause of the high limit condition. Refer to the diagnostic
service section at the end of this Installation and Operating Instructions Manual.