Lochinvar 81-286 No Display, No Burner, Operation, Unit Does, Not Modulate, Above 50%

FAULT

CAUSE

CORRECTIVE ACTION

- No 120 vac supplied to unit.

•

Check external line switch, fuse, or breaker.

•

Check position of ON/OFF switch. Turn switch to the

ON position.

• Check 120 vac through the ON/OFF switch.

• Check wiring

harness connection

between

display

board

and

main

control

board.

Connect

No Display

harness at both points.

- No voltage through the switch.

•

Replace switch.

- Bad display board.

•

Replace board.

- Bad main control board.

•

Replace the main control board.

- Blown fuse.

•

Replace

fuse

F3 on

the main

control

board, see

page 33 of this manual.

- Main control board temperature set point

•

Review temperature setting.

satisfied.

- Remote thermostat satisfied.

•

Review remote thermostat setting.

No Burner

- Outside air temperature above Warm

•

Check

location of

outside

air

sensor.

Check

Weather Shutdown (WWSD) set point for

resistance of outdoor air sensor and compare to Table

Operation

main control board.

3-2B on page 35 of this manual.

•

Consult

display for

specific

fault.

Refer

to fault

- Unit locked out on fault.

descriptions on page 37 of this manual for corrective

actions.

- Unit in Shutdown Mode.

• Take unit out of Shutdown Mode.

•

Check ramp delay parameter settings. Optional PC

- Ramp delay active.

software required.

•

Turn ramp delay feature off.

See page 23 of this

Unit Does

manual for instructions on how to turn this feature off.

• Check BMS parameter settings. Optional PC

Not Modulate

- Boiler controlled by BMS.

software required.

Above 50%

•

Verify that the flue sensor is located in the flue outlet.

- Flue sensor open.

•

Check wiring connections at the flue sensor.

•

Check the resistance of the flue sensor and compare

to Table 3-2D on page 35 of this manual.