750-211 (revised 2009)
Promethean Boilers, Model 4WI Manual
4-1
CHAPTER 4
Sequence of Operation
4.1 — Overview
This chapter outlines the electrical sequencing of various controls through the pre-purge, ignition, run, and shut-
down cycles of the burner.
The program relay establishes the sequence of operation and directs the operation of all other controls and compo-
nents to provide an overall operating sequence.
The burner and control system are in starting position when the following conditions exist:
•
Boiler water is up to the correct level, closing the low-water cutoff switch, and the auxiliary low water cutoff, if
applied.
•
The low-water light (panel) is off.
•
The operating limit pressure control (steam boiler) or the operating limit temperature control (hot water boiler)
and high limit pressure or temperature control switches are closed.
•
All other limit circuit switches are closed.
•
The load demand light glows.
•
All entrance panel switches are closed and power is present at the line terminals corresponding to:
a. Blower motor starter.
b. Air compressor motor starter (if provided).
c. Oil heater relay (if provided).
d. Oil pump motor starter (if provided).
Chapters 6 and 7 contain operating instructions and specific information on setting and adjusting the controls.
NOTE:
The make or model of the program relay provided will vary depending upon job specifications. The following
sequence applies regardless of the make or model. Please refer to the Wiring Diagram (WD) prepared by Cleaver-
Brooks for your specific installation.
Summary of Contents for 4WI
Page 46: ...Burner Operation and Control 2 22 750 211 revised 2009 Promethean Boilers Model 4WI Manual...
Page 62: ...Waterside Care and Requirements 3 16 750 211 revised 2009 Promethean Boilers Model 4WI Manual...
Page 70: ...Sequence of Operation 4 8 750 211 revised 2009 Promethean Boilers Model 4WI Manual...
Page 114: ...Adjustment Procedures 6 28 750 211 revised 2009 Promethean Boilers Model 4WI Manual...
