Lennox SL25XPV Series

©2021 Lennox Industries Inc.
Dallas, Texas, USA
Page 1
General
This SL25XPV outdoor air conditioner with all-aluminum
coil is designed for use with HFC-410A refrigerant only.
These instructions are intended as a general guide and do
not supersede local codes in any way. Consult authorities
having jurisdiction before installation.
INSTALLATION
INSTRUCTIONS
HEAT PUMP
508104-01
4/2021
Dave Lennox Signature
®
Collection SL25XPV System
WARNING
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, personal
injury or loss of life. Installation and service must be
performed by a licensed professional HVAC installer or
equivalent, or service agency.
IMPORTANT: Special procedures are required for clean-
ing the all-aluminum coil in this unit. See page 22 in this
instruction for information.
CONTROL
PANEL ACCESS
LOCATION
6 (152)
36 (914)
12 (305)
30 (762)
24
(610)
LINE SET
CONNECTIONS
ACCESS
PANEL
REAR VIEW OF UNIT
48 (1219)
MINIMUM CLEARANCE BETWEEN TWO UNITS
CLEARANCE ON ALL SIDES — INCHES (MILLIMETERS)
MINIMUM CLEARANCE
ABOVE UNIT
NOTES:
Clearance to access panel must be 30
inches (762mm).
Clearance to one of the other three
sides must be 36 inches (914mm).
Clearance to one of the remaining two
sides may be 12 inches (305mm) and
the final side may be 6 inches
(152mm).
Note: Dimensions are not to scale.
THIS UNIT IS A INTEGRAL COMPONENT OF A SYSTEM THAT
WILL REQUIRE A COMMUNICATING THERMOSTAT AND
COMMUNICATING AIR HANDLER OR FURNACE.
SL25XPV
Communicating air handler
or furnace
Communicating
thermostat
SETTING THE UNIT – Clearances
THIS MANUAL MUST BE LEFT WITH THE
HOMEOWNER FOR FUTURE REFERENCE
PACKING LIST
OUTDOOR UNIT
WARRANTY
CARD
GROMMETS (2)
BUSHING (1)
RAST 6-PIN
CONNECTOR (1)
This unit must be installed with an approved indoor air
handler or coil. For AHRI Certied system match-ups and
expanded ratings, visit www.LennoxPros.com.

Lennox SL25XPV Series Specifications

General

Compressor Type	Variable Speed
Refrigerant	R-410A
Energy Star Certified	Yes
Stages	Variable
Smart Technology	iComfort®-enabled
Cooling Capacity (BTU/h)	Up to 60, 000
Warranty	10-Year Limited Warranty on covered components
Sound Rating	As low as 59 dB

Summary

General Installation Information

General Safety Warnings

Highlights critical safety warnings for installation and operation.

Unit Placement and Refrigerant Piping

Refrigerant Piping Introduction

Details requirements for matching indoor coils and handling old refrigerants.

Refrigerant Piping Safety and Regulations

Covers refrigerant handling regulations and pressure safety.

Refrigerant Charging for Long Line Sets

Heat Pump System Guidelines

Provides line set length and lift guidelines for HFC410A systems.

Refrigerant Line Set Specifications

Brazing Safety Precautions

Highlights hazards associated with brazing alloys and fire risk.

Removing Existing Indoor Metering Device

Fixed Orifice Removal Procedure

Step-by-step instructions for removing a fixed orifice metering device.

Expansion Valve Removal Procedure

Step-by-step instructions for removing an expansion valve.

Flushing Procedures

Connecting Gauges for Flushing

Diagram and steps for connecting equipment for flushing.

Flushing Line Set

Procedure for flushing the line set and indoor unit coil.

Brazing Procedures for Refrigerant Piping

Line Set Preparation and Valve Cap Removal

Steps for preparing refrigerant lines and removing valve caps.

Attaching Manifold Gauge Set

Instructions for connecting the manifold gauge set for brazing.

Brazing Procedures - Continued

Wrapping Service Valves

Protects service valve seals during brazing using water-saturated cloths.

Nitrogen Flow for Brazing

Details the procedure for flowing nitrogen during brazing.

Brazing the Line Set

Instructions for brazing liquid and suction/vapor lines.

Installing Indoor Expansion Valve

Expansion Valve Installation Steps

Guide for installing the check/expansion valve at the indoor coil.

Leak Test and Evacuation

Leak Testing Procedure

Steps for connecting gauges and testing the system for leaks.

System Evacuation

Evacuation Gauge Set Connection

System Evacuation Process

Evacuation Safety Warning

Warns against deep vacuum operation and compressor damage.

Electrical Wiring and Circuit Sizing

Electrical Safety and ESD Precautions

Covers electrical hazards, fire risks, and electrostatic discharge protection.

Unit Start-Up Procedures

Professional Maintenance Checks

Coil Cleaning Guidelines

General System Performance Test

Start-Up and Performance Checklist