Iv. Starting The Unit; A. Sequence Of Operations - Thermo Pride CHX3-75N Installation And Operation Manual

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

IV. STARTING THE UNIT

A. SEQUENCE OF OPERATIONS

AT ANY TIME THE
GAS VALVE IS
NOT ENERGIZED
THERMOSTAT CALLS FOR
ENERGIZED ON HIGH SPEED
SWITCHES SENSES ADEQUATE
DIFFERENTIAL PRESSURE,
PREPURGE IGNITION DELAY,
INDUCER RUNS FOR 15 SECONDS
PRESSURE DIFFERENTIAL,
CONTACTS STAY CLOSED
SILICON NITRIDE IGNITOR.
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
HEAT W1 OR W1 & W2,
CONTACTS CLOSE
50V51-843 CONTROL
ENERGIZED, INDUCER
LOW FIRE PRESSURE
CONTACTS CLOSE
INDUCER REDUCES
TO LOW SPEED
LOW PRESSURE SWITCH
SENSES ADEQUATE
POWER IS APPLIED TO
THE WHITE RODGERS
IGNITOR WARM-UP IS
17 SECONDS
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