Weil-McLain SERIES 7 PFG - Manual (Page 12)

12
PFG S
erieS
7 G
aS
-
Fired
W
ater
B
oiler
– U
niverSal
C
ontrol
S
yStemS
Part Number 550-110-643/0605
Check for open thermostat or circ. relay
(where used) or check for loose wire
connections, defective spill switch or
rollout thermal fuse element, or open
LWCO or limit contacts.
If LWCO, spill switch or
rollout thermal fuse element
contacts are open, determine cause
and correct condition. Failure to do so
will cause severe personal injury, death,
or substantial property damage.
Open thermostat contacts for 15 seconds. Close thermostat
contacts - is 24 VAC across terminals PV & MV/PV?
No Yes
Replace ignition control.
Is 24VAC present across Terminals 24V & 24V(GND)?
No Yes
VISUALLY CHECK - is ground wire connected from
"GND(Burner)" to ignition control mounting screw;
and ground wire connected from transformer
Terminal "C" to case ground?
No Yes
Correct by making connections.
Turn OFF supply voltage.
Check spark wire. Is it securely connected
to spark transformer?
No Yes Securely connect, then turn ON supply voltage and re-test.
Is condition of spark wire good (not cut,
brittle, burned, or cracked)?
No Yes
Is spark gap 0.125" and isolated in pilot gas steam?
No Yes
Replace pilot assembly.
Replace pilot assembly, turn ON supply
voltage, operate system several complete
heat cycles.
Replace ignition control.
Replace pilot assembly, turn ON supply
voltage, operate system several
complete heat cycles.
TABLE I: No Spark, System Does Not Work
Without Vent Damper
Is spark electrode ceramic cracked?
No Yes