Control Timings - Bradford White TTW 75 SERIES Service Manual

Control Timings

Ignition State
Pre-purge
Trial for Ignition
Flame Stabilization Period
Inter-purge
Flame Failure Response Time
Post-purge
PS Fault Delay (failed open/close)
Soft Lockout
TCO Limit Lockout
Verify Resistive Delay
Simulated Resistive Load Lockout
Hardware Error Lockout
8
2 Seconds
90 Seconds
3 Seconds
15 Seconds
1.5 Seconds (2 second. Maximum; 1 second minimum.)
15 Seconds
Retry after 2 Minutes
Retry after 5 Minutes
Indefinite (cycle power to restart)
Retry after 2 Minutes (repeats 5 times)
Indefinite (cycle power to restart)
Indefinite (self clears if fault clears for at least 15 seconds)
Wiring Diagram
Blower
Temperature
Switch
Pressure
Switch
Blower
Housing
Pilot
C
B
A
Simulated
Resistive
Device
Thermal
Well
Specifications
Timing
Blower
Motor
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