Thermo Products CMA2-75N ユーザーズマニュアル

All installations and services must be performed by qualified service personnel.

V. STARTING THE UNIT

A. SEQUENCE OF OPERATIONS

START

TRIAL

FOR

IGNITION

CONTINUOUS SAFE OPERATION CHECK

IF FLAME SIMULATION CONDITION

PRESENT OR ROLL-OUT SWITCH OPENS, SYSTEM

ENERGIZES INDUCER FAN FOR 15 SECONDS AND CIRCULATOR BLOWER AT

HEATING SPEED UNTIL SITUATION CORRECTION

THERMOSTAT CALLS FOR

HEAT, CONTACTS CLOSE

POWER INTERRUPTION

SYSTEM SHUTS OFF,

RESTARTS WHEN POWER

IS RESTORED.

PRESSURE SWITCH SENSES

ADEQUATE DIFFERENTIAL PRESSURE,

CONTACTS CLOSE

CONTROL BOARD ENERGIZED,

INDUCER ENERGIZED

POWER IS APPLIED TO

THE SILICON NITRIDE

IGNITOR. IGNITOR

WARM-UP IS 20 SECONDS.

AFTER IGNITOR WARM-UP,

THE GAS VALVE IS

ENERGIZED TO OPEN

FLAME MUST BE DETECTED

WITHIN 4 SECONDS IF

FLAME IS DETECTED, THE

DELAY-TO-FAN-ON TIME

BEGINS (45 SECONDS)

IF FLAME IS NOT DETECTED, THE

GAS VALVE IS DE-ENERGIZED,

THE IGNITOR IS TURNED OFF AND

THE CONTROL BOARD CONTROL GOES

INTO "RETRY" SEQUENCE.

START

AT ANY TIME THE

GAS VALVE IS

NOT ENERGIZED