Burnham V8 Series Instructions.pdf - Heating Help

Figure 19: Wiring Diagram, Steam, Standard Hydrolevel CG450 Probe LWCOBOILER SEQUENCE OF OPERATION WITH PROBE LWCOWhen the thermostat calls for heat, it energizes the R8239C Control Center relay which in turn energizes the cad cellprimary control, bringing on the burner. The burner will operate in the following sequence: Prepurge for the first 10seconds; fire until the thermostat is satisfied or the limit setting on the high limit is reached; post-purge for the last 10seconds. When the high limit control restores the circuit on a drop in pressure, the burner will start if the thermostat isstill calling for heat.The probe low water cut-off will shut down the burner after a 10-15 second delay, if the water level in the boiler dropsbelow the probe level.The Hydrolevel CG450 low water cut-off will shut down the burner for 90 seconds every 10 minutes of firing time toallow water level to stabilize. If the water level is too low the burner will not be allowed to restart.The probe low water cut-off will reset and restart the burner with a call for heat a few seconds after the water is returnedto its normal level.On burner start, if the cad cell does not see flame within approximately 15 seconds, primary control will shut burnerdown 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 beforeburner can be restarted.When there is no demand for heat, the operating control will maintain the boiler water temperature at the selectedsetting for proper operation of the domestic water heater, if equipped with optional tankless heater.38