Riello GAS 7 P/M Installation, Use And Maintenance Instructions Download

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BURNER STARTING DIFFICULTIES AND

THEIR CAUSES

The symbol, visible on the reading disc of the pointer,
shows the kind of problem.



The control box does not start at the thermostats

     closing, because of:
-  lack of gas;
-  the gas pressure switch does not close the contact:

bad set;

- the air pressure switch changed over in operation

position;

- the control box fuse is broken;
- the servomotor does not totally change over the

closing circuit in being between the terminals 11 and
8 of the control box.



Stop at the start-up, because of:

- the servomotor does not change over the max.

opening circuit in being between the terminals 9 and
8 of the control box.



Lock-out

The air pressure switch does not change over, because
of:
- defective

contact;

- insufficient pressure of the air.



Lock-out

Unperfect operation of the flame detecting circuit,
because of:
- probe

earth;

- defective

internal

amplifier.



Stop during pre-purge phase, because of:

The servomotor does not change over the minimal
opening circuit in being between the terminals 10 and 8
of the control box.



Lock-out due to flame signal lack; if:

-  the ionisation probe is not inside of the flame;
-  the probe connection to the control box is
    disconnected;
-  the ionization current is insufficient (min. 6 µA).



Lock-out during operation due to:

- flame

signal

lack;

- no air pressure.

NOTICE

- If lock-out occurs between the start-up and the pre-

ignition phase without that a symbol comes out, the
cause is the flame simulation.

- If the burner repeats continuously the start-up cycle

without lock-out occurring, this is due to the
“oscillation” of the gas pressure switch caused by a
setting very near to the gas network pressure,
therefore the pressure decreasing at the burner start-
up is sufficient to actuate the gas pressure switch
causing a new start-up.

SAFETY TEST - WITH GAS BALL VALVE CLOSED

It is fundamental to ensure the correct execution of the
electrical connections between the gas solenoid valves
and the burner to perform safely the commissioning.

For this purpose, after checking that the connections
have been carried out in accordance with the burner's

electrical diagrams, an ignition cycle with closed gas
ball valve -dry test- must be performed.
1

The manual ball gas valve must be closed

The electrical contacts of the burner limit switch
need to be closed

Ensures closed the contact of the low gas pressure
switch

Make a trial for burner ignition

The start-up cycle must be as follows:
–

Starting the fan for pre-ventilation

–

Performing the gas valve seal control, if provided

–

Completion of pre-ventilation

–

Arrival of the ignition point

–

Power supply of the ignition transformer

–

Electrical Supply of solenoid gas valves

Since the manual gas ball valve is closed, the burner
will not light up and its control box will go to a safety
lockout condition.
The actual electrical supply of the solenoid gas valves
can be verified by inserting a tester. Some valves are
equipped with light signals (or close/open position
indicator) that turn on at the same time as their power
supply.

SAFETY COMPONENTS

The safety components must be replaced at the end of
their life cycle indicated in the table. The specified life
cycles do not refer to the warranty terms indicated in the
delivery or payment conditions.

IF THE ELECTRICAL SUPPLY OF THE GAS
VALVES OCCURS AT UNEXPECTED TIMES, DO
NOT OPEN MANUAL GAS BALL VALVE, SWITCH
OFF POWER LINE; CHECK THE WIRES;
CORRECT THE ERRORS AND REPEAT THE
COMPLETE TEST.

Safety component

Life cycle

Flame control

10 years or 250,000

operation cycles

Flame sensor

10 years or 250,000

operation cycles

Gas valves (solenoid)

10 years or 250,000

operation cycles

Pressure switches