Roberts Gorden COMBAT CTU 22 TO 115 - Manual (Page 40)

COMBAT ® CTU U NIT H EATERS I NSTALLATION O PERATION AND S ERVICE M ANUAL
34
15.3 Troubleshooting for Flame Supervision System
Repair or replace as
necessary.
Control box faulty.
Replace with correct type.
Use section 15.1 to
trace the fault.
Heater Operating
TROUBLESHOOT ENDS.
No
Repair or replace as
necessary.
Is inlet burner gas pressure
correct? Is live and neutral
polarity correct? Is
flame probe circuit correct?
Is there a current flowing in the
flame probe circuit with no
flame present?
Yes
No
Does “lockout” occur when
there is a flame present?
Yes
Is the connecting lead
damaged? Is the flame probe
damaged or touching earthed
components?
No
Is the green light on and
at least 1 µA DC flame
current?
Connect a DC ammeter in
series with the flame probe.
Yes
No
Yes
Yes
No
START
If problems persist, contact
ROBERTS GORDON ® at
Tel: +44(0) 121 506 7709
www.rg-inc.com
NOTE: Minimum flame probe current 1 μA DC. Typical flame probe current 3-5 μA DC.
15.4 Troubleshooting for Solenoid Valves
Valve faulty.
Replace with one of
correct type.
Fault elsewhere
Fault elsewhere
Valve Operating
TROUBLESHOOT ENDS.
No
Yes
Valve faulty.
Replace with one of
correct type.
Does gas pressure at
outlet of valve return to zero or
lower when valve turns off?
No
Yes
Does gas pressure at outlet
of the valve rise when
valve turns on?
No
Yes
Is gas pressure at inlet of the
valve correct for gas type?
Note pressure found.
No
Yes
START
Is 230 V at the valve
terminals at the
appropriate time.
Yes
No
If problems persist, contact
ROBERTS GORDON ® at
Tel: +44(0) 121 506 7709
www.rg-inc.com