Installation / Operation Instruction Manual

Table Of Contents
Page 111
10.E.2 Pre-purge Closed
In Pre-purge Closed mode, the boiler/heater blower will
turn on and run at Pre-Purge Speed. The boiler/heater
veries that the APS transitions from open to closed.
The gas valve and spark are o󰀨. The duration of this
mode is dened by the Pre-Purge APS Closed Time. If
the APS closes and the Pre-Purge APS Closed Time
expires, the boiler/heater will transition to Transition
to Pre-Ignition mode. If the APS remains open, or if
there is a separate lock-out condition, the boiler/heater
transitions to the Lock-out mode. If the call for heat is
removed, the boiler/heater will transition to Standby
mode.
NOTE:
The duration of pre-purge is established to
ensure proper evacuation of any unspent fuel in
the combustion chamber and ue collector.
10.E.3 Transition to Pre-Ignition
In Transition to Pre-Ignition mode, the boiler/heater
blower will modulate to the Ignition Speed. The gas
valve and spark are o󰀨. Once the blower is maintaining
the Ignition Speed, the heater/blower will transition to
Pre-Ignition mode.
NOTE: The purpose of Transition to Pre-Ignition is to
allow time for the blower to ramp down to the
Ignition Speed prior to Pre-Ignition.
10.E.4 Pre-Ignition
In Pre-Ignition the boiler/heater blower will maintain
the Ignition Speed, the gas valve is o󰀨. The spark is
energized for the duration of the Pre-Ignition Time.
With the boiler/heater maintaining the Ignition Speed,
once the Pre-Ignition Time expires, the heater/boiler will
transition to Pilot Ignition mode. If there is a lock-out
condition in this mode, the boiler/heater will transition to
the Lock-out mode. If the call for heat is removed, the
boiler/heater will transition to Standby mode.
10.E.5 Pilot Ignition
In Pilot Ignition mode, the blower continues to run at
Ignition Speed and the main gas valve remains o󰀨. The
spark continues to be energized and the pilot valve
is energized. The pilot gas valve is energized for the
duration of the Pilot Flame Establishing Period. The
pilot ame must be observed and present above the
lower ame threshold prior to the expiration of the
Pilot Flame Establishing Period. After the Pilot Flame
Establishing Period has expired and ame signal is
equal to or above the Flame Signal Lower Threshold,
the boiler transition to Main Ignition mode. If proper
ignition does not occur, and the maximum attempts for
ignition has not occurred, the boiler/heater will transition
to Inter-Purge mode. If proper ignition does not occur,
and the maximum attempts for ignition has been
reached, the boiler/heater will transition to Lock-out
mode. If the call for heat is removed, the boiler/heater
will transition to Standby mode.
NOTE:
Three attempts for ignition, prior to lock-out, is
standard. CSD-1 units have a single attempt
for ignition prior to lock-out.
10.E.6 Main Ignition
In Main Ignition mode, the blower continues to run at
Ignition Speed, the spark is de-energized and the pilot
valve remains energized. If the ame signal continues
to be equal to or greater than the Flame Signal Lower
Threshold, then the main gas valve is energized for the
Main Flame Establishing Period. Proper ignition has
occurred if the ame signal is greater than or equal to
the Flame Signal Lower Threshold prior to the Main
Flame Establishing Period expiring. If proper ignition
has been established, the boiler/heater will transition
to Run mode. If proper ignition does not occur, and
the maximum attempts for ignition has not occurred,
the boiler/heater will transition to Inter-Purge mode.
If proper ignition does not occur, and the maximum
attempts for ignition has been reached, the boiler/heater
will transition to Lock-out mode. If the call for heat is
removed, the boiler/heater will transition to Standby
mode.
NOTE: Three attempts for ignition, prior to lock-out, is
standard. CSD-1 units have a single attempt
for ignition prior to lock-out.
10.E.7 Run
In Run mode, the blower will then modulate to the
required speed (RPM or %) and the main gas valve
remains energized. If there is a loss of ame during
Run mode, the boiler/heater will transition to Inter-Purge
mode. If a lock-out condition occurs during Run mode,
the boiler/heater will transition to Lock-out mode. If the
call for heat is removed, the boiler/heater will transition
to the Post-Purge prior to returning to Standby mode.