Lochinvar Sync Condensing Boiler 1.3 - Manual (Page 43)

3
Troubleshooting
(continued)
Label all wires prior to disconnection
when servicing controls. Wiring errors can
cause improper and dangerous operation.
Always disconnect power to the boiler
before servicing. Failure to comply could
result in severe personal injury, death, or
substantial property damage.
Never jumper (bypass) any device except
for momentary testing as outlined in the
Troubleshooting chart. Severe personal
injury, death, or substantial property
damage can result.
Before troubleshooting:
1. Have the following items:
a. Voltmeter that can check 120 VAC, 24 VAC, and
12 VDC.
b. Continuity checker.
c. Contact thermometer.
2. Check for 120 VAC (minimum 102 VAC to maximum
132 VAC) to boiler.
3. Make sure thermostat is calling for heat and contacts
(including appropriate zone controls) are closed. Check
for 24 VAC between thermostat wire nuts and ground.
4. Make sure all external limit controls are installed and
operating.
Check the following:
1. Wire connectors to control module are securely plugged
in at the control module and originating control.
2. Gas pressures:
• Maximum: 14 inches w.c. (3.5 kPa) natural,
14 inches w.c. (3.2 kPa) LP with no flow (lockup)
or with boiler on
• Minimum: 4 inches (5 inches on 1.0 models only) w.c.
(1.0 kPa) natural, 8 inches w.c. (2.0 kPa) LP with gas
flowing (verify during boiler startup)
Check control module fuses
ALWAYS check control module fuses
before replacing control module or any
major components (blower, etc.). If one
of these fuses is blown, it can prevent the
control module or other components from
operating.
1. Turn OFF the power to the boiler at the external line
switch.
2. Remove the front access cover.
3. Remove the two (2) screws securing the control panel to
the unit to gain access to the control module.
F4 - 3.15 AMP FUSE
BLOWER
F3 - 1.25 AMP FUSE
MAIN BOARD
F5 - 5 AMP FUSE
PUMPS
F2 - 3.15 AMP FUSE
24V SUPPLY
Figure 3-1 Control Module Fuses
6. The boiler is shipped with six (6) spare fuses in a plastic
bag located under the low water cutoff on the control
module.
7. If necessary, replace open fuse (F3 is 1.25 amps, F2 and F4
are 3.15 amps, and F5 is 5 amps).
Note: Fuses F2 - F5 are all slow blow fuses.
Do not jumper fuse or replace with any
fuse except as specified. Failure to comply
could result in severe personal injury,
death, or substantial property damage.
8. Re-install the control module cover using the nuts
removed in Step 4.
Note: If the spark wire was unplugged, reattach it to the
control.
9. Re-install the control panel using the two (2) screws
removed in Step 3. Re-install the front access cover after
fuse inspection.
10. Restore power to the boiler at the external line switch
and verify boiler operation (Section 9 - Start-up in the
SYNC Boiler Installation and Operation Manual) after
completing boiler service.
ƽ WARNING
ƽ WARNING
NOTICE
ƽ WARNING
Service Manual
43
4. Remove the two (2) nuts on the control module cover.
5. Inspect fuses F2, F3, F4, and F5, see FIG 3-1.