Lennox Merit ML17XC1 Series User Manual

©2022 Lennox Industries Inc.
Dallas, Texas, USA
Page 1
THIS MANUAL MUST BE LEFT WITH THE
HOMEOWNER FOR FUTURE REFERENCE
General
This ML17XC1 outdoor air conditioner with all-aluminum
coil is designed for use with HFC-410A refrigerant only.
This unit must be installed with an approved indoor air han-
dler or coil. For AHRI Certied system match-ups and ex-
panded ratings, visit www.LennoxPros.com.
These instructions are intended as a general guide and do
not supersede local codes in any way. Consult authorities
having jurisdiction before installation.
NOTICE!
Charging information is given on the charging
procedure sticker on the unit access panel. For more in-
depth information, consult the Installation and Service
Procedures manual on LennoxPros.com or through the
Technical Support department at 800-453-6669.
INSTALLATION
INSTRUCTIONS
AIR CONDITIONER
508254-01
4/2022
Merit
®
Series ML17XC1 Units
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.
CAUTION
As with any mechanical equipment, contact with sharp
sheet metal edges can result in personal injury. Take
care while handling this equipment and wear gloves and
protective clothing.
IMPORTANT: Special procedures are required for clean-
ing the all-aluminum coil in this unit. See page 15 in this
instruction for information.
STEP 1 – SETTING THE UNIT – Clearances
NOTES -
Service clearance of 30 in. (762 mm) must be maintained on one of
the sides adjacent to the control box.
Clearance to one of the other three sides must be 36 in. (914 mm).
Clearance to one of the remaining two sides may be 12 in. (305
mm) and the final side may be 6 in. (152 mm).
A clearance of 24 in. must be maintained between two units.
48 in. (1219 mm) clearance required on top of unit.
See
NOTES
See NOTES
See NOTES
See
NOTES
CONTROL
BOX
NOTICE: Specific applications may require adjustment of the listed installation clearances to provide protection for
the unit from physical damage or to avoid conditions which limit operating efficiency. (Example: Clearances may
have to be increased to prevent snow or ice from falling on the top of the unit. Additional clearances may also be
required to prevent air recirculation when the unit is installed under a deck or in another tight space.)
FIGURE 1

Lennox Merit ML17XC1 Series Specifications

General

Compressor Type	Single-stage
Refrigerant	R-410A
Energy Star Certified	Yes
Cooling Stages	1
Cooling Capacity	1.5 - 5 Tons
SEER Rating	17
Compressor	Scroll
Cabinet	PermaGuard™ Cabinet
Warranty	5-Year Limited Parts

Summary

STEP 1 – SETTING THE UNIT

Clearances

Specifies required clearances for proper unit installation and airflow.

Unit Placement

Details on placing the unit on a level surface or slope.

STEP 2 – REFRIGERANT PIPING

Flushing Existing Line Set & Indoor Coil

Procedures for flushing existing line sets and indoor coils.

LIQUID LINE FILTER DRIER INSTALLATION

Procedure for installing the liquid line filter drier.

LINE SET INSTALLATION

Guidance on properly installing and isolating refrigerant line sets.

Removing Existing Indoor Metering Device

Steps for removing existing fixed orifice or expansion valve.

Install Indoor Expansion Valve

Instructions for installing the indoor expansion valve unit.

Brazing Procedures

Detailed steps for brazing refrigerant line set connections.

Install Indoor Expansion Valve

Further instructions for installing the indoor expansion valve.

STEP 3 - LEAK TEST AND EVACUATION

TEST FOR LEAKS

Method for performing a leak test on the system.

EVACUATE THE SYSTEM

Steps for achieving system evacuation using a vacuum pump.

STEP 4 – ELECTRICAL – Circuit Sizing and Wire Routing

High Voltage and Field Control Wiring

Wiring diagrams and procedures for high voltage and control wiring.

STEP 5 - UNIT START-UP

Checking and Adding System Charge

Guidance on checking and adjusting refrigerant system charge.

ML17XC1 Start-Up and Performance Checklist

A checklist for verifying start-up and performance parameters.

Homeowners Information

Homeowner Maintenance

Recommended maintenance tasks for homeowners.

Professional Maintenance

Pre-Service Check

Checks to perform before calling for professional service.

Outdoor Unit

Professional inspection points for the outdoor unit.

Indoor Unit

Professional inspection points for the indoor unit.

General System Test

Procedures for testing the system's overall operation.