Table of Contents
Advertisement
Quick Links
©2023 Lennox Industries
Inc. Dallas, Texas, USA
THIS MANUAL MUST BE LEFT WITH THE
HOMEOWNER FOR FUTURE REFERENCE
NOTICE !
For more in-depth information, consult the Installa
tion and Service Procedures manual, available as
Corp. 1502-L7 on LennoxPros.com or through the
Technical Support Department at 800-453-6669.
STEP 1 -- SETTING THE UNIT -- Clearances
See
NOTES
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.)
See NOTES
See
NOTES
CONTROL
See NOTES
BOX
INSTALLATION
INSTRUCTIONS
®
Merit
Series ML14XC1 Units
AIR CONDITIONERS
507524-02
9/2023
Improper installation, adjustment, alteration, service or
maintenance can cause personal injury, loss of life, or
damage to property.
Installation and service must be performed by a licensed
professional installer (or equivalent) or a service agency.
GENERAL
This ML14XC1 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
handler or coil. See the Lennox ML14XC1 Product
Specifications bulletin (EHB) for approved indoor
component match ups.
These instructions are intended as a general guide and do
not supersede local codes in any way. Consult authorities
having jurisdiction before installation.
IMPORTANT: Special procedures are required for
cleaning the aluminum coil in this unit. See page 15 in this
instruction for information.
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.
FIGURE 1
Page 1
WARNING
Advertisement
Table of Contents
Related Manuals for Lennox Merit ML14XC1-018-230A
Summary of Contents for Lennox Merit ML14XC1-018-230A
- Page 1 HFC-410A refrigerant only. This unit must be installed with an approved indoor air THIS MANUAL MUST BE LEFT WITH THE handler or coil. See the Lennox ML14XC1 Product HOMEOWNER FOR FUTURE REFERENCE Specifications bulletin (EHB) for approved indoor component match ups.
-
Page 2: Step 1 -- Setting The Unit
NOTICE ! UNIT DIMENSIONS - INCHES (MM) Roof Damage! This system contains both refrigerant and oil. Some rubber roofing material may absorb oil, causing the rubber to degrade. Failure to follow this notice could result in damage to roof surface. IMPORTANT ! Exhaust vents from dryers, water heaters and fur... - Page 3 The protector will reset when low pressure rises tion. Take care to empty all existing traps. Polyol es above 40 psig. DO NOT REPLACE COMPRESSOR. ter (POE) oils are used in Lennox units charged with HFC-410A refrigerant. Residual mineral oil can act LIQUID LINE FILTER DRIER INSTALLATION as an insulator, preventing proper heat transfer.
-
Page 4: Installation
LINE SET IMPORTANT — Refrigerant lines must not contact structure. INSTALLATION REFRIGERANT LINE SET — INSTALLING Line Set Isolation - The following illustrations are VERTICAL RUNS (NEW CONSTRUCTION SHOWN) examples of proper refrigerant line set isolation: NOTE - Insulate liquid line when it is routed through areas where the surrounding ambient temperature could become higher than the REFRIGERANT LINE SET —... - Page 5 STEP 2 -- REFRIGERANT PIPING -- Removing Existing Indoor Metering Device TYPICAL EXISTING FIXED ORIFICE TYPICAL EXISTING EXPANSION VALVE REMOVAL REMOVAL PROCEDURE PROCEDURE (UNCASED COIL SHOWN) (UNCASED COIL SHOWN) STUB END TWO-PIECE PATCH PLATE LIQUID LINE DISTRIBUTOR TUBES (UNCASED COIL ONLY) ORIFICE EXPANSION LIQUID LINE ORIFICE HOUSING...
-
Page 6: Cap And Core Removal
STEP 2 -- REFRIGERANT PIPING -- Brazing Procedures CAP AND CORE REMOVAL CUT AND DEBUR Cut ends of the refrigerant lines square (free from nicks or dents) Remove service cap and core from and debur the ends. The pipe must remain round. Do not crimp end both the suction and liquid line service of the line. -
Page 7: Braze Line Set
WRAP SERVICE VALVES To help protect service valve seals during brazing, wrap water-saturated cloths around service valve bodies and copper tube stubs. Use additional water-saturated cloths underneath the valve body to protect the base paint. FLOW NITROGEN Flow regulated nitrogen (at 1 to 2 psig) through the refrigeration gauge set into the valve stem port connection on the liquid service valve and out of the suction valve stem port. - Page 8 STEP 2 -- REFRIGERANT PIPING -- Installing Indoor Expansion Valve This outdoor unit is designed for use in systems that use either an fixed orifice (RFC) (included with outdoor unit), or expansion valve metering device (purchased separately) at the indoor coil. See the ML14XC1 Product Specifications bulletin (EHB) for approved expansion valve kit match ups.
-
Page 9: Step 3 -- Leak Test And Evacuation
STEP 3 -- LEAK TEST AND EVACUATION LEAK TEST HIGH MANIFOLD GAUGE SET TO SUCTION SERVICE VALVE (ANGLE OR BALL TYPE) NITROGEN OUTDOOR UNIT HFC-410A CONNECT GAUGE SET A - Connect the high pressure hose of an HFC-410A manifold gauge set to the suction valve service port. - Page 10 STEP 3 -- LEAK TEST AND EVACUATION (CONTINUED) EVACUATION HIGH CONNECT GAUGE SET NOTE - Remove cores from service valves (if not already done). A - Connect low side of manifold gauge set with 1/4 SAE in-line tee to suction line service valve B - Connect high side of manifold gauge set to MANIFOLD...
-
Page 11: Install Thermostat
STEP 4 -- ELECTRICAL -- Circuit Sizing and Wire Routing In the U.S.A., wiring must conform with current local codes WARNING and the current National Electric Code (NEC). In Canada, wiring must conform with current local codes and the current Fire Hazard. - Page 12 STEP 4 -- ELECTRICAL (CONTINUED) -- High Voltage and Field Control Wiring The following illustration provide an example of control wiring connections when using standard thermostat. ROUTING HIGH VOLTAGE, GROUND AND CONTROL WIRING HIGH VOLTAGE / GROUND WIRES FIELD CONTROL WIRING Any excess high voltage field wiring should be THERMOSTAT INDOOR UNIT...
-
Page 13: Step 5 -- Unit Start-Up
TABLE 3 STEP 5 -- UNIT START-UP TORQUE REQUIREMENTS IMPORTANT Parts Recommended Torque Service valve cap 8 ft.- lb. 11 NM If unit is equipped with a crankcase heater, it should be Sheet metal screws 16 in.- lb. 2 NM energized 24 hours before unit start-up to prevent Machine screws #10 28 in.- lb. -
Page 14: Operating Angle-Type Service Valve
1/12 turn clockwise. NOTE The filter and all access panels must be in place any time the unit is in operation. If you are unsure about the filter required for your system, call your Lennox dealer for FIGURE 17 assistance. Page 14... - Page 15 (less than 50psi). If the coil cannot be Pre-Service Check cleaned using water alone, Lennox recommends If your system fails to operate, check the following before use of a coil cleaner with a pH in the range of 5 to 9.
-
Page 16: Start Up Checks
General System Test with System Operating charge per the charging sticker information on the outdoor unit. 1 - Your technician should perform a general system test. He will turn on the air conditioner to check operating 2 - Verify that system total static pressure and airflow functions such as the startup and shutoff operation.