Lennox SLP99DFV Series User Manual

Page 23
Integrated Control Diagnostic Codes (Continued)
Code Diagnostic Codes/Status of Equipment Action Required to Clear and Recover
E402
LSOM - Outdoor unit system pressure trip. Compressor ran over 18 hours in air conditioning mode.
E403
LSOM - Compressor short-cycling (Running less than
4 minutes).
Outdoor unit pressure trip. Check dirty coil, fan motor,
refrigerant charge.
E404
LSOM - Compressor rotor locked. Compressor short cycling (Running less than 4 minutes).
E405
LSOM - Compressor open circuit. Check capacitor, wiring, hard start kit , replace
Compressor.
E406
LSOM - Compressor open start circuit. Check compressor for hot (cool down) , check pressures,
fan motor etc. Replace compressor if unable to get circuit
to close and compressor to operate.
E407
LSOM - Compressor open run circuit.
E408
LSOM - Compressor contactor is welded.
E409
LSOM - Compressor contactor is welded. Replace contactor.
TABLE 15
OPERATING SEQUENCE
SLP99DFV and Single-Stage Outdoor Unit
OPERATING
SEQUENCE
SYSTEM DEMAND SYSTEM RESPONSE
System
Condition
Step
Demand Relative Humidity
Compressor
Blower
CFM
(COOL)
Comments
1st
stage
O G 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%
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 thermostat 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%
door unit energized after
point has been reached in
order to maintain room
humidity setpoint.
On-board links 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.
*CS
7500 thermostat only

Lennox SLP99DFV Series Specifications

General

Brand	Lennox
Model	SLP99DFV Series
Category	Furnace
Language	English