38
Fig. 61 — 62X Sequence of Operations Flow Chart, Heating Mode
IS HEAT
SOURCE GAS?
NO
IS SYSTEM
IN ALARM OR
SHUTDOWN?
YES
alarm in Equipment
Touch. See IOM For more
YES
NO
HEATING WILL MODULATE TO
MAINTAIN LAT HEATING SET POINT
IF SF VFD INCLUDED, VFD WILL
MODULATE TO 80% DURING GAS
FURNACE START-UP PURGE CYCLE
GAS FURNACE START-UP
PURGE CYCLE – 2 MINUTES
SF AND GAS FURNACE
RETURN TO NORMAL
OPERATION
FROM FIG. 58
DCM —
Digital Compressor Module
OADA —
Outdoor Air Damper/Actuator
EF
—
Exhaust Fan
OD
—
Outside Air Damper
HGRH —
Hot Gas Reheat
SF
—
Supply Fan
IOM
—
Installation and Operation Manual
SLT
—
Suction Line Temperature
LAT
—
Leaving Air Temperature
VFD —
Variable Frequency Drive
MDV —
Modulating Discharge Valve