Install Instructions

33
EMP
Installation & Service Manual
109529-03 - 11/19
Figure 23: Schematic Wiring Diagram
BOILER SEQUENCE OF OPERATION
A call for heat by the thermostat energizes the boiler control which in turn energizes the primary control to turn on the burner. The burner will operate in the following sequence: Prepurge for the first 10 seconds; fire until the thermostat is satisfied or the limit setting on the operating (high) limit is reached; post-purge for the last 10 seconds. The circulator will operate as long as the thermostat is calling for heat. If the thermostat is not satisfied and the operating (high) limit is reached, the circulator will continue to operate, and the burner will stop until the operating (high) limit is closed by a 15ºF drop in boiler water temperature. On burner start, if the cad cell does not see flame within approximately 15 seconds, primary control will shut burner down and enter into a recycle mode, after 60 seconds burner will restart and repeat trial for ignition. If after three (3) trials for ignition, flame is not detected, control will enter into restricted mode and must be reset manually before burner can be restarted.
6 Electrical (continued)