Troubleshooting - Weil-McLain WM97+100 Manual

WM97+ Series 2

Troubleshooting

Before calling for troubleshooting assistance, fi ll in the
" WM97+ Gas Data Collection Sheet
Record the boiler size and CP number (located on the
inside left side of the jacket above the heat exchanger).
Failure to adhere to these guide-
lines can result in severe per-
sonal injury, death or substantial
property damage.
ELECTRICAL SHOCK HAZARD
The boiler ON/OFF switch does not turn off all
power to the boiler.
TURN OFF ALL POWER TO
THE BOILER WHEN SERVICING
is still powered when the switch is off.
DO NOT JUMPER DEVICES
Never jumper (bypass) any device except for mo-
mentary testing.
REINSTALL JACKET DOOR
The boiler front door must be securely fastened to the
boiler to prevent boiler from drawing air from inside
the boiler room. This is particularly important if the
boiler is located in the same room as other appliances.
Failure to keep the door securely fastened could result
in severe personal injury or death.
BEFORE SERVICING or
MAKING CONNECTIONS —
ALWAYS TURN POWER OFF TO THE BOILER
TO PREVENT ELECTRICAL SURGES, WHICH
CAN DAMAGE BOILER COMPONENTS.
LABEL WIRES BEFORE
REMOVING
Label all wires prior to disconnection
when servicing controls. Wiring er-
rors can cause improper and danger-
ous operation.
– 106 –
-
GAS FIRED WATER BOILER
" ( page 144 ).
1. See Figure 111 for tools and kits recommended for troubleshoot-
2. Check for 120VAC (minimum 102 VAC to maximum 132 VAC)
3. Check the WM97+ control's last three lockout histories. (Navigate
Figure 111
. Internal wiring
Tool
#2 Phillips screwdriver
10 mm wrench
#20 long-handled Torx
driver
#25 Torx driver
Multimeter
Manometer
(Inclined or digital)
Combustion analyzer
(Digital preferred)
Contact thermometer
Maintenance kit
Check the following:
1. Make sure thermostat is calling for heat and contacts (including
2. Make sure all external limit controls are either installed (and
3. Make sure that connectors to WM97+ control are securely
4. Gas pressures:
— Boiler Manual
ing WM97+ boilers.
to boiler.
to the DIAGNOSTICS menus.)
a. See Figure 87, page 77 for navigation instructions and Fig-
ure 96, page 86 for the complete Diagnostics menus.
b. In the DIAGNOSTICS menu, scroll down to ERRORS and
press the enter key.
c. Record the fi rst four data records and then highlight the history
record you want to view.
d. Follow information at the bottom of the screen to navigate
through your lockout histories.
Tools and kits needed for troubleshooting
Purpose
Multiple uses
Remove heat exchanger cover plate
Remove burner screws
To remove gas valve
Measurements on sensors and electrical components
Measure the INLET gas pressure to the boiler
Combustion testing and boiler adjustments
Checking surface temperatures of heat exchanger and
pipes
ALWAYS have this kit on hand when performing main-
tenance in case replacement is required.
appropriate zone controls) are closed. Check for 24VAC between
thermostat wire nuts and ground.
closed) or temporarily jumpered for testing.
plugged in at module and originating control.
Maximum: 13" (330 mm) w.c. with no fl ow (gas valve lockup
pressure).
Minimum: must be no less than the minimum values given
on page 21 while operating on high fi re.
Part number 550-142-204/0117