Weil-McLain EGH-125 - Manual (Page 28)

EGH-105 to EGH-125 EGH-105 to EGH-125 EGH-105 to EGH-125 EGH-105 to EGH-125 EGH-105 to EGH-125
Control Supplement
Part Number 550-110-677/0299 28
Check-out procedure — troubleshooting
VIII
Is damper harness securely plugged in at both ends? Secure connections.
Is 24VAC present across transformer terminals C & Y?
Check for open thermostat, circulator relay, operating
control, limit control or LWCO. Check the CSD-1 control
panel, impulse relay and push-button switch.
If limit controls or water level controls
lockout on manual reset, determine cause
and correct condition. Failure to do so could
result in severe personal injury, death or
substantial property damage.
Check for out of round stack section. Does motor rotate
open?
Is 24VAC present across terminal C and yellow wire on
damper connector?
Is 24VAC present across terminals PV and MV/PV?
Open thermostat contacts for 30 seconds. Damper will
rotate to closed position. Close thermostat contacts.
Damper will rotate to open position. Is 24VAC present
across terminals PV and MV/PV?
Remove damper harness from
boiler wiring harness.
TEMPORARILY install jumper
between terminal 2 and
terminal 5 on damper plug in
boiler wiring harness. See
figure below. Does boiler fire?
No Yes
No Yes
TS-2: No Spark — System (boiler with vent damper) does not work
Check for loose wire connections or bad relay on
transformer.
No Yes
Is damper rotated open?
No Yes
No Yes
Replace actuator.
Retest.
Check continuity of each wire in wiring harness to
damper. Does continuity exist for each wire?
Replace damper
wiring harness.
Retest.
Replace ignition
control. Retest.
Is spark present now?
No Yes
Retest.
No Yes
No Yes
No Yes
No Yes
1
4
2
5
3
6
Replace damper
actuator. Retest.
Temporary
jumper
Securely connect
and turn ON supply
voltage. Retest.
Check spark wire. Is it securely
connected to ignition control?
No Yes
Replace pilot
assembly. Retest.
Is condition of spark wire good
(not brittle, burned or cracked)?
No Yes
Is spark electrode
ceramic cracked?
No Yes
Is spark gap 0.125" and
located in pilot gas stream?
Replace
pilot
assembly.
Replace ignition
control. Retest. Replace pilot
assembly.
Turn ON supply voltage and operate
system several complete cycles.
No Yes
Turn OFF supply voltage.
Electrical shock hazard. Failure to turn off
power before proceeding could cause
severe personal injury or death.