Page 39
TABLE 15
OPERATING SEQUENCE
SL280UHV, Non-Communicating Thermostat with Humidity Control Feature and Single-Speed Outdoor Unit
OPERATING SEQUENCE
SYSTEM DEMAND
SYSTEM RESPONSE
System
Condition
Step
Thermostat Demand
Relative Humidity
Compre
ssor
Blower
CFM
(cool)
Comments
Y1
O
G
W1
Status
D
NO CALL FOR DEHUMIDIFICATION
Normal Operation
1
On
On
On
Acceptable
24
VAC
High
100%
Compressor and
indoor blower follow
thermostat demand
BASIC MODE (only active on a Y1 thermostat demand)
Normal Operation
1
On
On
On
Acceptable
24
VAC
High
100%
ComfortSense® 7500
thermostat energizes
Y1 and de-energizes
D on a call for de-
humidification
Dehumidification
call
2
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
High
100%
Dehumidification
mode begins when
humidity is greater
than set point
Dehumidification
Call
2
On
On
On
Demand
0 VAC
High
70%
Dehumidification
Call Only
1
On
On
On
Demand
0 VAC
High
70%
ComfortSense®
7500 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 single stage outdoor unit. 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 ComfortSense® 7000 thermostat to use for this application - Y2081 4 heat / 2 cool
*Dehumidification blower speed is 70% of COOL speed for all units .
**In Precision mode, ComfortSense® 7000 thermostat will maintain room temperature up to 2 °F (1.2°C) cooler than room setting.
