Lennox EL297UH090XV36C - Page 47

Page 47
TABLE 11
OPERATING SEQUENCE
Non-Communicating Thermostat with Humidity Control Feature and Two-Speed Outdoor Unit
OPERATING
SEQUENCE
SYSTEM DEMAND SYSTEM RESPONSE
System
Condition
Step
Thermostat Demand Relative Humidity
Compre
ssor
Blower
CFM
(cool)
Comments
Y1 Y2 O G W1 W2 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%
CS7500 thermostat
energizes Y1 and de-
energizes D on a call for
de-humidication
Dehumidication
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%
Dehumidication mode
begins when humidity is
greater than set point
Dehumidication
Call
2 On On On On Demand
0
VAC
High 70%
Dehumidication
Call Only
1 On On On On Demand
0
VAC
High 70%
CS
7500 thermostat
will try to maintain
room humidity setpoint
by allowing the room
space to maintain a
cooler room thermostat
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%
CS7500 thermostat
energizes Y2 and de-
energizes D on a call for
de-humidication
Dehumidication
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%
Dehumidication mode
begins when humidity is
greater than set point
Dehumidication
Call
2 On On On On Demand
0
VAC
High 70%
Dehumidication
Call ONLY
1 On On On On Demand
0
VAC
High 70%
CS7500 thermostat
will try to maintain
room humidity setpoint
by allowing the room
space to maintain a
cooler room thermostat
setpoint***
Jumpers at indoor unit with a two stage outdoor unit
Cut factory jumper from Y1 to Y2 or cut W915 (Y1 to Y2)
With Condensing unit - Cut W914 (R to DS) on SureLight® control
With Heat Pump - Cut W914 (R to DS) & W951 (R to O) on SureLight® control
Dave Lennox CS7000 thermostat to use for this application - Y2081 4 heat / 2 cool
*Normal operation rst stage cooling blower speed is 70% COOL speed.
**Dehumidication blower speed is, reduced to 70% of COOL.
***In Precision mode, CS
7000 thermostat will maintain room temperature up to 2 °F (1.2°C) cooler than room setting.