user manual

ManualsBrandsLennox International Inc. ManualsAir ConditionerAir Conditioner CONDENSING UNITS

07/11 506645−01

*2P0711* *P506645-01*

Page 1

2011 Lennox Industries Inc.

Dallas, Texas, USA

RETAIN THESE INSTRUCTIONS

FOR FUTURE REFERENCE

These instructions are intended as a general guide and do

not supersede local codes in any way. Consult authorities

who have jurisdiction before installation.

WARNING

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.

IMPORTANT

The Clean Air Act of 1990 bans the intentional venting of

refrigerant (CFCs, HCFCs and HFCs) as of July 1, 1992.

Approved methods of recovery, recycling or reclaiming

must be followed. Fines and/or incarceration may be

levied for noncompliance.

IMPORTANT

This unit must be matched with an indoor coil as

specified in Lennox Engineering Handbook. Coils

previously charged with HCFC−22 must be flushed.

NOTICE TO INSTALLER

UNIT PLACEMENT

It is critical for proper unit operation to place outdoor unit on an

elevated surface as described in Unit Placement section on page 7.

BRAZING LINE SET TO SERVICE VALVES

It is imperative to follow the brazing technique illustrated starting on

page 11 to avoid damaging the service valve’s internal seals.

INSTALLATION

INSTRUCTIONS

Merit

Series 14ACX Units

CONDENSING UNITS

506645−01

07/11

Supersedes 11/10

TABLE OF CONTENTS

Shipping and Packing List 1. . . . . . . . . . . . . . . . . . . . . . . .

General 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Unit Dimensions 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Typical Unit Parts Arrangement 3. . . . . . . . . . . . . . . . . . .

Model Number Identification 3. . . . . . . . . . . . . . . . . . . . . .

Operating Manifold Gauge Set and Service Valves 4. . .

Recovering Refrigerant from Existing System 6. . . . . . .

New Unit Placement 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Removing and Installing Louvers 8. . . . . . . . . . . . . . . . . .

New or Replacement Line Set 9. . . . . . . . . . . . . . . . . . . . .

Brazing Connections 11. . . . . . . . . . . . . . . . . . . . . . . . . . .

Flushing Line Set and Indoor Coil 14. . . . . . . . . . . . . . . .

Installing Indoor Metering Device 15. . . . . . . . . . . . . . . .

Leak Test Line Set and Indoor Coil 16. . . . . . . . . . . . . . .

Evacuating Line Set and Indoor Coil 17. . . . . . . . . . . . .

Electrical Connections 18. . . . . . . . . . . . . . . . . . . . . . . . . .

Servicing Unit Delivered Void of Charge 22. . . . . . . . . . .

Unit Start−Up 22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

System Refrigerant 22. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

System Operation 28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Maintenance 28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Start−Up and Performance Checklist 30. . . . . . . . . . . . . .

Shipping and Packing List

Check the unit for shipping damage and listed times below

are intact. If damaged, or if parts are missing, immediately

contact the last shipping carrier.

1  Assembled outdoor unit

1  Refrigerant flow control kit (fixed orifice)

1  Liquid line filter drier

General

14ACX Air Conditioners, which will also be referred to in

this instruction as the outdoor unit, uses HFC−410A

refrigerant. This outdoor unit must be installed with a

matching indoor unit and line set as outlined in the Lennox

14ACX Engineering Handbook.

This outdoor unit is designed for use in systems that use

one of the following refrigerant metering devices:

 Thermal expansion valve (TXV)

 Fixed orifice

Litho U.S.A.

Summary of content (30 pages)

PAGE 1
INSTALLATION INSTRUCTIONS 2011 Lennox Industries Inc. Dallas, Texas, USA Merit® Series 14ACX Units CONDENSING UNITS 506645−01 07/11 Supersedes 11/10 RETAIN THESE INSTRUCTIONS FOR FUTURE REFERENCE These instructions are intended as a general guide and do not supersede local codes in any way. Consult authorities who have jurisdiction before installation. WARNING Improper installation, adjustment, alteration, service or maintenance can cause personal injury, loss of life, or damage to property.
PAGE 2
Unit Dimensions − Inches (mm) A A OUTDOOR COIL FAN DISCHARGE AIR COMPRESSOR B SUCTION AND LIQUID LINE CONNECTION OPTIONAL UNIT STANDOFF KIT (4) (FIELD INSTALLED) SIDE VIEW SIDE VIEW Model Numbers A B 14ACX−018−230 24−1/4 (616) 29−1/4 (743) 14ACX−024−230 28−1/4 (724) 33−1/4 (845) 14ACX−030−230 28−1/4 (724) 37−1/4 (946) 14ACX−036−230 28−1/4 (724) 37−1/4 (946) 14ACX−042−230 28−1/4 (724) 29−1/4 (743) 14ACX−041−230 and 14ACX−048−230 28−1/4 (724) 37−1/4 (946) 14ACX−059−230 32−1/4 (8
PAGE 3
Typical Unit Parts Arrangement NOTE Plumbing layout and compressor type may vary between model sizes.
PAGE 4
CAUTION IMPORTANT Physical contact with metal edges and corners while applying excessive force or rapid motion can result in personal injury. Be aware of, and use caution when working near these areas during installation or while servicing this equipment. To prevent stripping of the various caps used, the appropriately sized wrench should be used and fitted snugly over the cap before tightening. When servicing or repairing HVAC components, ensure the fasteners are appropriately tightened.
PAGE 5
Operating Angle Type Service Valve: 1. Remove stem cap with an appropriately sized wrench. 2. Use a service wrench with a hex−head extension (3/16" for liquid line valve sizes and 5/16" for vapor line valve sizes) to back the stem out counterclockwise as far as it will go.
PAGE 6
Recovering Refrigerant from Existing System Use the following procedure to recover refrigerant from an existing system (indoor coil, line set and outdoor unit). 1 2 CONNECT MANIFOLD GAUGE SET DISCONNECT POWER Disconnect all power to the existing outdoor unit at the service disconnect switch or main fuse box/breaker panel. Connect a gauge set, clean recovery cylinder and a recovery machine to the service ports of the existing unit.
PAGE 7
MINIMUM CLEARANCE ABOVE UNIT CLEARANCE ON ALL SIDES INCHES (MILLIMETERS) 6 (152) ACCESS PANEL NOTES: 30 (762) 12 (305) 48 (1219) 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). LINE SET CONNECTIONS 36 (914) MINIMUM CLEARANCE BETWEEN TWO UNITS ACCESS PANEL 24 (610) LINE SET CONNECTIONS Figure 4.
PAGE 8
PLACING UNIT ON SLAB When installing unit at grade level, the top of the slab should be high enough above grade so that water from higher ground will not collect around the unit. The slab should have a slope tolerance as described in figure 5, detail B. ROOF MOUNTING Install the unit at a minimum of 4 inches (102 mm) above the surface of the roof. Ensure the weight of the unit is properly distributed over roof joists and rafters. Redwood or steel supports are recommended.
PAGE 9
Recommended topping−off POE oils are Mobil EAL ARCTIC 22 CC or ICI EMKARATE RL32CF. New or Replacement Line Set This section provides information on new installation or replacement of existing line set. If a new or replacement line set is not required, then proceed to Brazing Connections on page 11. Field refrigerant piping consists of liquid and suction lines from the outdoor unit (braze connections) to the indoor unit coil (flare or braze connections).
PAGE 10
LINE SET IMPORTANT Refrigerant lines must not contact structure. INSTALLATION REFRIGERANT LINE SET INSTALLING VERTICAL RUNS (NEW CONSTRUCTION SHOWN) Line Set Isolation The following illustrations are 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 temperature of the liquid line or when pressure drop is equal to or greater than 20 psig.
PAGE 11
Brazing Connections Use the procedures outline in figures 9 and 10 for brazing line set connections to service valves. IMPORTANT Polyol ester (POE) oils used with HFC−410A refrigerant absorb moisture very quickly. It is very important that the refrigerant system be kept closed as much as possible. DO NOT remove line set caps or service valve stub caps until you are ready to make connections.
PAGE 12
1 CUT AND DEBUR Cut ends of the refrigerant lines square (free from nicks or dents) and debur the ends. The pipe must remain round. Do not crimp end of the line. 2 CAP AND CORE REMOVAL Remove service cap and core from both the suction / vapor and liquid line service ports.
PAGE 13
4 5 6 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 / vapor valve stem port.
PAGE 14
Flushing Line Set and Indoor Coil Flushing is only required if existing indoor coil and line set are to be used. Otherwise proceed to Installing Indoor Metering Device on page 15.
PAGE 15
Installing Indoor Metering Device 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. coil. In applications where an uncased coil is being installed in a field−provided plenum, install the expansion valve in a manner that will provide access for field servicing of the expansion valve.
PAGE 16
Leak Test Line Set and Indoor Coil IMPORTANT IMPORTANT The Environmental Protection Agency (EPA) prohibits the intentional venting of HFC refrigerants during maintenance, service, repair and disposal of appliance. Approved methods of recovery, recycling or reclaiming must be followed. Leak detector must be capable of sensing HFC refrigerant. After completing the leak testing the line set and indoor coil as outlined in figure 13, proceed to Evacuating Line Set and Indoor Coil on page 17.
PAGE 17
Evacuating Line Set and Indoor Coil CONNECT GAUGE SET 1 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 vapor line service valve B Connect high side of manifold gauge OUTDOOR set to liquid line service valve UNIT C Connect micron gauge available connector on the 1/4 SAE in−line tee. A D Connect the vacuum pump (with vacuum gauge) to the center port of the manifold gauge set.
PAGE 18
WARNING Danger of Equipment Damage. Avoid deep vacuum operation. Do not use compressors to evacuate a system. Extremely low vacuums can cause internal arcing and compressor failure. Damage caused by deep vacuum operation will void warranty. defined as any gas that will not condense under temperatures and pressures present during operation of an air conditioning system. Non−condensables and water suction combine with refrigerant to produce substances that corrode copper piping and compressor parts.
PAGE 19
ROUTING HIGH VOLTAGE/ GROUND AND CONTROL WIRING HIGH VOLTAGE / GROUND WIRES Any excess high voltage field wiring should be trimmed and secured away from any low voltage field wiring. To facilitate a conduit, a cutout is located in the bottom of the control panel. Connect conduit to the control panel using a proper conduit fitting. LOW VOLTAGE CONTROL WIRING NOTE For proper voltages, select thermostat wire (control wires) gauge per table above.
PAGE 20
HIGH PRESSURE SWITCH (S4) LIQUID LINE CRANKCASE HEATER (HR1) CRANKCASE THERMOSTAT (S40) Figure 16.
PAGE 21
THERMAL PROTECTION SWITCH (S5 OR S173) HIGH PRESSURE SWITCH (S4) LIQUID LINE CRANKCASE HEATER (HR1) CRANKCASE THERMOSTAT (S40) Figure 17.
PAGE 22
2. Inspect all factory− and field−installed wiring for loose connections. 3. After evacuation is complete, open the liquid line and suction line service valve stems (Operating Service Valves on page 4) to release the refrigerant charge (contained in outdoor unit) into the system. 4. Replace the stem caps and tighten to the value listed in table 1. 5. Check voltage supply at the disconnect switch. The voltage must be within the range listed on the unit’s nameplate.
PAGE 23
CHECKING AIR FLOW AT INDOOR COIL Check airflow using the Delta−T (DT) process using the illustration in figure 19. Temp. of air entering indoor coil ºF DT 24 23 22 21 72 20 20 19 18 17 17 16 15 15 14 13 12 11 10 70 Wet−bulb ºF 19 19 18 18 17 17 16 15 15 14 13 12 11 10 57 58 59 60 61 62 63 64 65 66 67 68 69 70 A Dry−bulb 80 78 76 74 24 23 22 21 24 23 22 21 23 22 21 20 23 22 21 19 22 21 20 19 22 21 19 18 22 20 19 17 20 19 18 16 19 18 17 16 18 17 16 15 17 16 15 14 16 15 14 13 1.
PAGE 24
WEIGH IN (RFC AND TXV) CALCULATING SYSTEM CHARGE FOR OUTDOOR UNIT VOID OF CHARGE If the system is void of refrigerant, first, locate and repair any leaks and then weigh in the refrigerant charge into the unit. To calculate the total refrigerant charge: Amount specified on nameplate Adjust amount. for variation in line set length listed on line set length table below. Total charge + = Refrigerant Charge per Line Set Length Liquid Line Set Diameter Ounces per 5 feet (g per 1.5 m) adjust from 15 feet (4.
PAGE 25
65ºF (18.3ºC) and above USE WEIGH-IN METHOD Weigh-in or remove refrigerant based upon line length ABOVE or BELOW 64ºF (17.7ºC) and below BLOCK OUTDOOR COIL: [sometimes necessary with lower temperatures] Use cardboard or plastic sheet to restrict the airflow through the outdoor coil to achieve pressures from 325−375 psig (2240−2585 kPa). Higher pressures are needed to check charge.
PAGE 26
START: Measure outdoor ambient temperature USE WEIGH-IN METHOD Weigh-in or remove refrigerant based upon line length SUPERHEAT RFC 40ºF (4.4ºC) and Above 1. Confirm proper airflow across coil using figure 19. 2. Compare unit pressures with table 4, Normal Operating Pressures. 3. Use SUPERHEAT to correctly charge unit or to verify the charge is correct. 4. Set thermostat to call for heat (must have a cooling load between 70-80ºF (21−26ºC) 5. Connect gauge set. 6.
PAGE 27
Table 4. HFC−410A Normal Operating Pressures (Liquid +10 and Suction +5 psig) Use this table to perform maintenance checks; it is not a procedure for charging the system. Minor variations in these pressures may be due to differences in installations. Significant deviations could mean that the system is not properly charged or that a problem exists with some component in the system. IMPORTANT Model −018 −024 −030 −036 −041 −042 −047 −048 −059/−060 **Temp.
PAGE 28
System Operation UNIT COMPONENTS IMPORTANT Some scroll compressor have internal vacuum protector that will unload scrolls when suction pressure goes below 20 psig. A hissing sound will be heard when the compressor is running unloaded. Protector will reset when low pressure in system is raised above 40 psig. DO NOT REPLACE COMPRESSOR.
PAGE 29
Indoor Unit 1. Clean or change filters. 2. Lennox blower motors are prelubricated and permanently sealed. No more lubrication is needed. 3. Adjust blower speed for cooling. Measure the pressure drop over the coil to determine the correct blower CFM. Refer to the unit information service manual for pressure drop tables and procedure. 4. Belt Drive Blowers − Check belt for wear and proper tension. 5. Check all wiring for loose connections. 6. Check for correct voltage at unit. (blower operating) 7.
PAGE 30
Start−Up and Performance Checklist Job Name Job no. Date Job Location City State Installer City State Unit Model No. Serial No. Service Technician Nameplate Voltage Rated Load Ampacity Compressor Outdoor Fan Maximum Fuse or Circuit Breaker Electrical Connections Tight? Indoor Filter clean? Supply Voltage (Unit Off) Indoor Blower RPM S.P. Drop Over Indoor (Dry) Outdoor Coil Entering Air Temp.