COMBAT CUHA - 8.3.2 Flame Supervision Systems - Manual Ignition; Section 8.4 Fault Finding for Solenoid Valves

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UNIT HEATER
STA RT
All controls ON
YES
NO
Is Green light ON ? Check for electrical supply
operation of external controls
YES & limit the rm ostat s
YES
Is RED lockout wa rning Press in reset button on
light ON ? control box or remote reset
NO
NO NO
Ignition spark operating ? Remove pilot burner as in 7.3 replace spark generator
& inspect electrode and
YES H.T. lea d. Re pla c e if faulty
NO YES
Pilot flame igniting Pilot solenoid valve opening ? Check gas is on
and purged of air
YES NO
NO
Use 8.4 to test solenoid valve Control box faulty
Repla c e
YES NO
Red "Lockout" light Check flame current is at Check Inlet pressure of gas
comes ON ? least 1 µ amps DC when is correct for gas type.
pilot ligh ts
YES YES
Remove pilot burner as in 7.3
inspect flame probe and
lea d. Replace if faulty
NO
Control box faulty
Replace with correct type.
NO NO
Main burner fires ? Check for 230v a t output Control box faulty
from control box Repla ce with corre ct type
YES
YES
Use 8.4 to check valves
YES
Burner operating
To measure flame current, connect
a 0 - 50 µA DC meter in series with
The flame probe by using the flame
probe jack plug.
If the meter reads Negative values
then reverse the test leads.
WARNING Ignition output from the
spark generator is 160 kv to earth.
Extreme care must be taken
8.2 Fault Finding For Automatic Ignition Burner Systems