Service Manual

3Troubleshooting (continued)

Table 3E (continued from previous page) Troubleshooting Chart - Fault Messages Displayed on Water Heater Interface

FAULT

 

DESCRIPTION

 

CORRECTIVE ACTION

 

 

 

 

 

The unit was running and lost the flame

• Inspect spark electrode and associated wiring for

 

signal.

This condition occurred four (4)

damage and connection.

Reference page 19 of this

 

straight times.

manual for removal and cleaning procedures. Replace

 

 

 

if necessary.

 

 

 

 

 

Exception: Models 500 - 800 will lock out

• Check for proper electrical grounding of unit.

 

 

after one retry for ignition. It will require a

 

 

manual reset before attempting to fire again.

• Check

incoming

supply

gas pressure. Natural gas

 

 

 

pressures should be between 4 -

14 inches

w.c. and

 

 

 

LP gas pressures should be between 8 - 14 inches w.c.

 

 

 

Refer to Section 7 - Gas Connections of the Armor

 

 

 

Water Heater Installation and Operation Manual for

 

 

 

detailed information concerning the gas supply.

 

 

 

• Verify that the plastic hose from the gas valve to the air

 

 

 

inlet is connected and is not damaged.

 

 

 

 

• Verify that the vent/air intake pipes are installed

 

 

 

correctly and there are no obstructions.

 

No Flame

 

 

• Check for 24 VAC to the gas valve at the 2-pin

 

 

connection on the side of the main control board during

Running

 

 

the ignition attempt. If no voltage is present, replace the

(will require a manual

 

 

main control board.

 

 

 

 

 

 

 

 

 

 

 

reset once the condition

 

 

• If 24 VAC is present at the main control board, check

has been corrected.

 

 

 

 

the wiring between the main control board and the gas

Press the RESET button

 

 

 

 

valve.

Replace

the wiring if

necessary.

Do not

on the SMART

 

 

 

 

disconnect the wiring from the gas valve and attempt to

SYSTEM display to

 

 

 

 

measure voltage at that point. The main control board

reset.)

 

 

 

 

can detect if the gas valve is not connected and will

 

 

 

 

 

 

display the GV / Relay Fail fault.

 

 

 

 

 

• If 24 VAC is present, check the outlet of the valve to

 

 

 

ensure the valve is flowing gas. With a manometer

 

 

 

connected to the outlet tap of the gas valve, when the

 

 

 

unit is in the prepurge period, there should be a

 

 

 

negative pressure present. When the valve is

 

 

 

energized a change in pressure should occur. If the

 

 

 

pressure change does not occur, the gas valve is not

 

 

 

opening. Replace the gas valve.

 

 

 

 

 

• Inspect

flame

sensor

and

associated

wiring.

 

 

 

Reference page 19 of this manual for removal and

 

 

 

cleaning procedures. Replace if necessary.

 

 

 

 

• Inspect the burner. Reference page 19 of this manual

 

 

 

for removal and cleaning procedures. Replace if

 

 

 

necessary.

 

 

 

 

 

 

 

• Replace the main control board.

 

 

 

 

 

 

 

 

 

 

 

27

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Lochinvar 150 - 800 service manual No Flame, Running