Water Heater Operation (24 Volt only)
Thermostat calls for heat
Within 15 seconds:
•
Vent damper rotates to open position
•
Vent damper opening is confirmed and an electrical
signal is sent to the ignition system in the controller
Within 30 seconds:
•
Ignition system is powered and
•
Lights the pilot
•
Confirms pilot ignition
•
Allows the main valve to open
•
Burner ignites
At the end of the “On Cycle”:
•
The thermostat contacts open
•
The ignition system closes the gas valve
•
Burner shuts “off”
•
The vent damper starts to close
Within 30 seconds:
•
The vent damper is fully closed
System Error Codes for 24 Volt Controls
The micro-controller inside the gas control monitors the
TCO safety feature, the ignition sequence, temperature set-
tings and overall operation of the heater. If any of these
parameters does not operate properly the controller will shut
down the water heater, diagnose the failure and flash an
error code. Table 3 lists the system status Codes for the 24
Volt Honeywell control.
Note:
If a random power outage is experienced, your water
heater may experience a soft lockout for approximately 2
minutes. This lockout is required to allow the control to reset
itself.
If the gas control valve is submerged under water for any
length of time, the gas control valve assembly should be
replaced.
LED FLASH SEQUENCE
CONTROL STATUS
Short flash once
every four seconds
IDLE (no call for heat,
no fault conditions)
"Heartbeat", alternates
bright/dim
Call For Heat
(no fault conditions)
One Flash,
three second pause
Low Flame Signal
(control continues to operate)
Two Flash,
three second pause
End Switch Failed Closed
Three Flash,
three second pause
TCO or End Switch Failed Open
Four Flash,
three second pause
ECO Limit Lockout
Five Flash,
three second pause
Flame Out Of Sequence
Six-One Flash,
three second pause
Soft Lockout - Retry Limit -
Failed TFI
Six-Two Flash,
three second pause
Soft Lockout - Recycle Limit -
PS/Limit opened
Six-Three Flash,
three second pause
Soft Lockout - Recycle Limit -
Flame Lost
Six-Four Flash,
three second pause
Soft Lockout - Flame out of
Sequence Sensed
Seven Flash,
three second pause
Flammable Vapor Sensor
Lockout
Eight-One Flash,
three second pause
FVS Fault Detected
Eight-Two Flash,
three second pause
Temperature Sensor Fault
Detected
Eight-Three Flash,
three second pause
Electronics Fault Detected
Eight-Four Flash,
three second pause
Valve Fault Detected
Table 3
Status Codes (Honeywell)
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