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TABLE 27
OPERATING SEQUENCE
SLP99UHV and Two-Speed Outdoor Unit
OPERATING
SEQUENCE
SYSTEM DEMAND SYSTEM RESPONSE
System
Condition
Step
Thermostat Demand Relative Humidity
Compressor
Blower
CFM
(cool)
Comments
1st
stage
2nd
stage
O G Status D*
NO CALL FOR DEHUMIDIFICATION
Normal Operation
Y1
1 On On On Acceptable
24
VAC
Low 70%
Compressor and indoor blower
follow thermostat demand
Normal Operation
Y2
2 On On On On Acceptable
24
VAC
High 100%
ROOM THERMOSTAT CALLS FOR FIRST STAGE COOLING
BASIC MODE (only active on a Y1 thermostat demand)
Normal Operation 1 On On On Acceptable
24
VAC
Low 70%
Thermostat energizes 2nd stage
and de-energizes D on a call for
dehumidication
Dehumidication
call
2 On On On On Demand
0
VAC
High 70%
PRECISION MODE (operates independent of a Y1 demand)
Normal Operation 1 On On On Acceptable
24
VAC
Low 70%
Dehumidication mode begins
when humidity is greater than
set point
Dehumidication
Call
2 On On On On Demand
0
VAC
High 70%
Dehumidication
Call Only
1 On On On On Demand
0
VAC
High 70%
Thermostat will keep outdoor
unit energized after cooling
temperature setpoint has been
reached in order to maintain
room humidity setpoint.*
ROOM THERMOSTAT CALLS FOR FIRST AND SECOND STAGE COOLING
BASIC MODE (only active on a Y1 thermostat demand)
Normal Operation 1 On On On On Acceptable
24
VAC
High 100%
Thermostat energizes 2nd stage
and de-energizes D on a call for
dehumidication
Dehumidication
Call
2 On On On On Demand
0
VAC
High 70%
PRECISION MODE (operates independent of a Y1 thermostat demand)
Normal Operation 1 On On On Acceptable
24
VAC
Low 70%
Dehumidication mode begins
when humidity is greater than
set point
Dehumidication
Call
2 On On On On Demand
0
VAC
High 70%
Dehumidication
Call ONLY
1 On On On On Demand
0
VAC
High 70%
Thermostat will keep outdoor
unit energized after cooling
temperature set-point has been
reached in order to maintain
room humidity set-point.
On-board links at indoor unit with a two-stage outdoor unit:
Cut factory link from Y1 to Y2 or cut W915 (Y1 to Y2) on SureLight® integrated control.
With Condensing unit - Cut W914 (R to DS) on SureLight® integrated control;
With Heat Pump - Cut W914 (R to DS) & W951 (R to O) on SureLight® integrated control.
*ComfortSense® 7500 thermostat only