Troubleshooting - Lochinvar Power-fin 502 Service Manual

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Troubleshooting

Label all wires prior to disconnection when
WARNING
servicing controls. Wiring errors can cause
improper and dangerous operation. Always
disconnect power to the appliance before
servicing. Failure to comply could result in
severe personal injury, death, or substantial
property damage.
Never jumper (bypass) any device except for
WARNING
momentary testing as outlined in the
Troubleshooting chart.
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 appliance.
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 module and originating control.
2. Gas pressures:
Refer to Section 3 - Gas Connections of the Power-fin
Installation and Operation Manual for detailed information
concerning the gas supply.
Check control module fuses
NOTICE
1. Turn OFF the power to the appliance at the external line
switch.
2. Remove front access cover.
Severe personal
3. Inspect fuses F1, F2, F3, F5, and F6, see FIG. 3-1 below.
Figure 3-1_Control Module Fuses
4. The appliance is shipped with three (3) spare fuses in a
plastic bag attached to the control panel.
5. If necessary, replace open fuse (F1 and F6 are 1.6 amps, F3 is
3.15 amps, F2 and F5 are 5 amps).
Note: Fuses F1 - F6 are all slow blow fuses.
WARNING
6. Install front access cover after fuse inspection.
7. Restore power to the appliance at the external line switch
and verify boiler/water heater operation (Section 7 -
Start-up in the Power-fin Installation and Operation
Manual) after completing boiler/water heater service.
Service Manual
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
operating.
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.
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