Oilon GKP-50 MH, Operation And Maintenance Manual

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● Control unit during normal operation: the control unit adjusts the capacity controller
on its modulating range to correspond to the burner load. It does this by controlling
the air dampers and gas regulator.
● Control unit during manual operation: the burner operates at the capacity set by the
operator. The control unit shuts down the burner if it receives a shutdown signal
from boiler thermostat/pressure switch.
● Safety shutdown if the flame detection signal or air pressure is lost during operation.
● Safety shutdown if the gas pressure becomes too high during operation.
● Safety shutdown if the servomotors do not reach their position feedbacks during
operation.
● Safety shutdown if the gas pressure drops too much during operation.
● Safety shutdown if the safety circuit opens during operation.
● Safety shutdown if the boiler temperature or pressure limit switch is activated during
operation.
Controlled shutdown
● Servomotors drive to their minimum capacity position.
Afterburning begins
● Gas valve 1 closes (X01).
● Gas valve 2 closes (X02) with a delay (t12) after gas valve 1. Leak testing begins
when both valves are closed and the piping between them is emptied. (Gas valve 2
optional)
Post-purge begins
0023 ver. 2
● Leak testing for gas valves begins, if it is selected to be run during post-purge.
● Servomotors drive to their post-purge position.
● Safety shutdown if the control unit receives a flame detection signal.
● Fan motor stops at the end of the post-purge phase.
● The safety functions of the control unit are powered down at the end of the post-
purge phase.
● Servomotors drive to their standby position. Restart is possible when servomotors
have reached their standby position.
Lockout
● Servomotors drive to their standby position.
● Burner lockout is activated.
● After lockout, a manual reset is required in order to restart the burner.
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