Steady State Operation; Firing Failure; Undesired Shutdown During Operation; Final Checks - Riello RL 42 BLU Installation, Use And Maintenance Instructions

6.4.2

Steady state operation

System equipped with one control device TR
Once the starting cycle has come to an end, the command of the
nd
2 stage solenoid valve passes on to the control device TR that
controls boiler temperature or pressure.
➤ When the temperature or the pressure increases until the
control device TR opens, solenoid valve 11)(Fig. 25) opens,
and the burner passes from the 2
ation.
➤ When the temperature or pressure decreases until the con-
trol device TR closes, solenoid valve 11) closes, and the
burner passes from the 1
and so on.
➤ The burner stops when the demand for heat is less than the
amount of heat delivered by the burner in the 1
In this case, the remote control device TL opens, solenoid
valve 8) closes, the flame immediately goes out.
The fan's air damper valve closes completely.
System not equipped with control device TR (jumper wire in-
stalled)
The burner is fired as described in the case above.
If the temperature or pressure increase until control device TL
opens, the burner shuts down (section A-A in the Fig. 24).
When the solenoid valve 11) de-energizes, the piston 12) closes
nd
the passage to the 2 stage nozzle and the fuel contained in the
cylinder 15), piston B, is discharged into the return piping 7).
6.4.3

Firing failure

If the burner does not fire, it goes into lockout within 5 s of the
opening of the 1st nozzle valve and 30 s after the closing of con-
trol device TL.
The control box red pilot light will light up.
6.4.4

Undesired shutdown during operation

If the flame goes out during operation, the burner shuts down au-
tomatically within 1 second and automatically attempts to start
again by repeating the starting cycle.
6.5

Final checks

➤ Obscure the UV Sensor and switch on the control devices:
the burner should start and then lock-out about 10 s after
st
opening of the 1 stage operation valve.
➤ Obscure the UV Sensor while the burner is in operation:
it should follow the extinguishing of the flame within 1 s, the
repetition of the starting cycle and the burner's lock-out.
➤ Switch off control device TL followed by control device TS
while the burner is operating:
the burner should stop.
Start-up, calibration and operation of the burner
nd st
to the 1 stage of oper-
st nd
to the 2 stage of operation,
st
stage.
D1756
21 GB
Fig. 25
20023224