Lochinvar 3.5, 1.5, 2.5 service manual Troubleshooting, Before troubleshooting, Check the following

3 Troubleshooting

￿ WARNING	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.

￿WARNING 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 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:

•Maximum: 14 inches w.c. (3.5 kPa) (natural and LP) with no flow (lockup) or with boiler on

•Minimum: 4 inches w.c. (1.0 kPa) (natural and LP), with gas flowing (verify during boiler startup)

Service Manual

Check control module fuses

NOTICE	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 upper and lower doors.

3.Remove the four (4) screws securing the control panel cover to the unit to gain access to the control module.

4.Inspect fuses F2, F4, and F5, see FIG 3-1 below.

Figure 3-1Control Module Fuses

F2 - 3.15 AMP

BLOWER RELAYS

F4 - 5 AMP

PUMP RELAYS

F5 - 5 AMP

IGNITOR OUTPUT

F6 - 5 AMP

NOT USED

(SPARE)

5.The boiler is shipped with four (4) spare fuses in a plastic bag located inside the control panel.

6.If necessary, replace open fuse (F2 is 3.15 amps, F4, F5 and F6 are 5 amps each).

Note: Fuses F2, F4, F5 and F6 are all slow blow fuses.

￿WARNING 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.

7.Re-install the control panel cover using the four (4) screws removed in Step 3. Re-install the upper and lower doors after fuse inspection.

8.Restore power to the boiler at the external line switch and verify boiler operation (Section 9 - Start-up in the Crest Installation and Operation Manual) after completing boiler service.

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