Roberts Gorden CTCU 27 - Manual (Page 30)

COMBAT ® CTCU U NIT H EATER I NSTALLATION O PERATION AND S ERVICE M ANUAL
24
14.3 Troubleshooting for Flame Supervision System
Repair or replace as
necessary.
If problems persist, contact
Roberts-Gordon Ltd. at
www.rg-inc.com
Control box faulty.
Replace with correct type.
Use Section 14.1 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 flame present and
at least 1 µA DC flame
current?
Connect a DC ammeter in
series with the flame probe.
Yes
No
Yes
Yes
No
START
NOTE: Minimum flame probe current 1 μA DC. Typical flame probe current 3-5 μA DC.
To measure flame current, connect a 0 - 50 μA DC meter in
series with the flame probe. If the meter reads negative
values, then reverse the test leads.