Weil-McLain SERIES 7 PFG - Manual (Page 15)

15
PFG S
erieS
7 G
aS
-
Fired
W
ater
B
oiler
– U
niverSal
C
ontrol
S
yStemS
Part Number 550-110-643/0605
TABLE IV: Spark is Present, Pilot Will Not Light
With or Without Vent Damper
Connect securely to Terminals PV
and MV/PV on ignition control.
Are pilot valve connections CORRECT and securely fastened?
No Yes
Open manual hand valve.
Is manual hand valve open?
No Yes
Is inlet gas pressure at least 5.0"W.C. and not over 14.0"W.C.?
No Yes
Contact gas supplier to
correct gas pressure.
Is gas present at pilot burner assembly? CAUTION -
Remove MV wire from ignition control, use a match
taped to a long screwdriver or pilot lighter rod and
manually light pilot.
No Yes
Make sure gas cock is in "ON" position and pilot line is
not kinked or obstructed. Check for clean pilot orifice.
If OK, replace gas valve.
Replace pilot assembly.
Block any draft around boiler. Check for clean pilot orifice.
Is spark gap 0.125" and located in pilot gas stream?
No Yes
TO CHECK IGNITION SYSTEM GROUNDING FOR TABLE III, PAGE 14.
Nuisance shutdowns are often caused by poor or erratic ground.
• Check for good metal-to-metal contact between pilot burner bracket
and main burner, and between main burner and burner rest.
control mounting screw, and from "C" on transformer to transformer case ground.
Make sure connections are clean and tight. If wire is damaged or deteriorated,
replace with No. 18 ga. moisture-resistant, thermosplastic insulated wire with
105°C minimum rating.
• Check ground lead from GND (BURNER) terminal on ignition control to ignition
Pilot assembly and ignition control must share common ground with main burner.