Weil-McLain Evergreen EVG 110, Manual

Page: 114 / 144

Figure 100 Troubleshooting suggestions for EVG boilers — Fault displays, diagnostics and corrective actions
Troubleshooting
(continued)
Part number 550-100-191/0917
114
®
g
as-fired water boiler —
70/110/155
Boiler Manual
Display
Condition Diagnostics Corrective Action(s)
IGNITION
FAULT Boiler went through 5 ignition
attempts and never detected
fl ame or fl ame sense value
never reached minimum
threshold for boiler model. Automatically resets after 1 hour
or can be reset by performing
manual reset on boiler. Check condensate trap for blockage allowing condensate to accumulate
inside heat exchanger.
Check ignition cable connection.
Fouled, worn, bent, or faulty igniter.
Fouled igniters can be cleaned for additional use with steel wool.
Worn or badly fouled igniters should be replaced with the proper repair
part.
Igniter rods should be parallel with a 3.5mm (0.138 in) spark gap
EVG 70/110 or 4.8mm (0.189 in) spark gap on EVG 155.
NOTICE: Thin white deposits on the igniter are typical, but brown or
black deposits could be the result of fl ue gas recirculation. Thoroughly
inspect the venting system and termination for the possibility of leakage
or fl ue gas feedback into the air line.
Dirty burner and/or heat exchanger will cause high back pressure and
poor ignition.
Follow procedure in maintenance section of this manual to clean burner
and heat exchanger. Visual inspection of fl ueways may not be suffi
cient
to diagnose condition.
Check combustion settings on high and low fi re and adjust per setup
instructions if necessary.
Check incoming gas pressure with boiler off and at high fi re. Adjust
within limits on rating label.
Verify correct boiler model is selected in control and high altitude is
selected for installations 5,500 above sea level.
Check ignition cable resistance. Should measure 1000 Ohms (+/- 50
Ohms).
Check for fl ue pipe and intake pipe restrictions or blockage.
Check burner fasteners and gaskets.
Check venturi gaskets and proper venturi. (Propane models use diff erent
venturi’s).
OUTDOOR
SENSOR ERROR Outdoor temperature sensor
short or OPEN. Will automatically reset if the
condition clears.
Warning only. Supply Max is
targeted until ODT is restored, if
used for target adjustment.
Determine which sensors are suspect and measure their resistance
value and compare it to the values shown in Figure 92, page 108 . If the
resistance values are incorrect replace the temperature sensor. Refer to
repair parts section for proper part number.
Check wire harness for loose connections and pin engagement at sensor
connection, chassis mount connection through control housing, and
the control. Unplug connection at sensor and at control and check
continuity between ends.
If problem persists after checking items above, replace control. Refer to
repair parts section for kit number.
AIR PRESSURE
Switch Open Occurs when Air Pressure
connection is open. Reset using Manual Reset
screen on display. Check boiler size selected in control against boiler rating label. Correct if
necessary to select the proper boiler size.
Check the factory jumper on P7 connection as seen on
Figures 60, page 62 & Figure 61, page 63 .
Closure Switch
fault Proof of Closure connections
on P7 Pins 2 and 3 are open. Soft lockout for 3½ minutes
boiler retries. Each consecutive
failure adds 1 minute to
lockout time, up to 6½ minutes
maximum. None - Check jumper on correct pins and secure connection.
Flow switch attached - Check correct pump is on, check wiring to fl ow
switch and check switch is closing.
CAD - Check voltage to damper. Check damper is opening.