Lennox XC20-036-230-01, XC20-060-230-01, XC20-024-230-01, XC20-048-230-01 Installation And Service Procedure

INSTALLATION AND SERVICE

PROCEDURE

Service Literature

Elite Series

Corp. 1407-L10

August 25, 2015

IMPORTANT

XC20 units have refrigerant piping requirements that are unique to this unit. Size and install the refrigerant piping per table 2 (page 14) to ensure proper unit operation.

IMPORTANT:

Before applying any power (main or low voltage) to the outdoor unit, confirm that the iComfort Wi-Fi® or iComfort® S30 thermostat has software Version 2.1 or higher installed. (Reference the iComfort Wi-Fi® or iComfort® S30 thermostat manual.)

This unit is an integral component of a system that requires an iComfort Wi-Fi iComfort

XC20

or iComfort® S30 thermostat and

-enabled air handler or furnace.

iComfort Wi-Fi

thermostat

iComfort

thermostat

S30

iComfort

air handler or

furnace

-enabled

XC20

XC20 Units

TABLE OF CONTENTS

I. OVERVIEW

Model Number Identification 2....................

Typical Serial Number Identification 2..............

Specifications 2.................................

Electrical Data 3................................

Unit Dimensions 4..............................

Typical Unit Parts Arrangement 5.................

Operating Service Valves 7.......................

General 7.....................................

II. INSTALLATION

Unit Placement 9...............................

Removing and Installing Panels 12.................

New or Replacement Line Set 13..................

Brazing Connections 16...........................

Flushing the System 19...........................

Leak Testing the System 21.......................

Evacuating the System 21.........................

Electrical 24.....................................

Servicing Unit Delivered Void of Charge 29..........

Unit Start-Up 29.................................

III. SYSTEM OPERATION AND SERVICE

7-Segment Alert and System Status Codes 30.......

Outdoor Control Push-Button Operation 38..........

Configuring Unit 42...............................

Reconfiguring Outdoor Control using iComfort Wi-Fi iComfort

System Overview 43.............................

Maintenance 44..................................

Unit Wiring Diagrams 45..........................

Factory Wiring Diagrams 48.......................

Unit Sequence of Operations 50...................

Component Testing 53............................

System Refrigerant 75............................

Appendix - Charging Sticker ....................

S30 Thermostat 43.....................

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.

2015 Lennox Industries Inc.

Model Number Identification

I. OVERVIEW

Refrigerant Type

X = R-410A

Unit Type

C = AIR CONDITIONER

C 20 036

− −

230

Nominal Cooling Capacity

-02

Minor Revision Number

Ratings Revision Level

Voltage

230 = 208/230V-1ph-60hz

024 = 2 tons

Series

036 = 3 tons 048 = 4 tons 060 = 5 tons

Typical Serial Number Identification

Location Code

19 = Saltillo, Mexico

58 = Marshalltown, IA

Year Code

08 = 2008 09 = 2009 10 = 2010

8 09 C

05716

5 (or 6) Digit Unique Number

Month Code

A = January B = February C = March

Specifications

Unit Outdoor Fan

Model Number

XC20-024-230-01 72 65 7 lbs, 5 oz 4 22

Sound Rating Number (dB) Maximum Minimum

Factory Refrigerant

Charge

Number of Blades Diameter - inches.

Unit Outdoor Fan

Model Number

XC20-036-230-01 75 67 8 lbs, 6 oz 4 22

Model Number

XC20-048-230-01 77 68 10 lbs, 7 oz 4 22

Model Number

XC20-060-230-01 77 69 12 lbs, 1 oz 3 26

Tested according to AHRI Standard 270-2008 test conditions.

Factory refrigerant charge is sufficient for refrigerant line lengths up to 15 feet.

Sound Rating Number (dB) Maximum Minimum

Unit Outdoor Fan

Factory Refrigerant

Charge

Number of Blades Diameter - inches.

XC20

Electrical Data

208/230V-60 Hz-1 Ph

Unit Compressor Outdoor Fan (RPM varies with compressor RPM)

Model Number

Maximum

Over-

current

Protection

(amps)

Minimum

Circuity

Ampacity

XC20-024-230-01 30 19.1 13.0 13.0 1/6 2600 1500 700 400 60 25 2.8

Unit Compressor Outdoor Fan (RPM varies with compressor RPM)

Model Number

Maximum

Over-

current

Protection

(amps)

Minimum

Circuity

Ampacity

XC20-036-230-01 30 20.6 14.2 13.0 1/4 3600 3100 700 600 115 80 2.8

Unit Compressor Outdoor Fan (RPM varies with compressor RPM)

Model Number

Maximum

Over-

current

Protection

(amps)

Minimum

Circuity

Ampacity

XC20-048-230-01 50 29.1 21.0 20.0 1/3 4000 3000 800 600 160 70 2.8

Unit Compressor Outdoor Fan (RPM varies with compressor RPM)

Model Number

Maximum

Over-

current

Protection

(amps)

Minimum

Circuity

Ampacity

XC20-060-230-01 50 29.3 21.2 20.0 1/3 4325 2900 865 600 195 80 2.8

HACR type circuit breaker or fuse.

Refer to National or Canadian Electrical Code manual to determine wire, fuse and disconnect size requirements.

Rated

Load

Amps

(RLA)

Locked

Rotor Amps (LRA)

Motor

CFM RPM WATTS

MAX MIN MAX MIN MAX MIN

Load Amps (FLA)

208/230V-60 Hz-1 Ph

Rated

Load

Amps

(RLA)

Locked

Rotor Amps (LRA)

Motor

CFM RPM WATTS

MAX MIN MAX MIN MAX MIN

Load Amps (FLA)

208/230V-60 Hz-1 Ph

Rated

Load

Amps

(RLA)

Locked

Rotor Amps (LRA)

Motor

CFM RPM WATTS

MAX MIN MAX MIN MAX MIN

Load Amps (FLA)

208/230V-60 Hz-1 Ph

Rated

Load

Amps

(RLA)

Locked

Rotor Amps (LRA)

Motor

CFM RPM WATTS

MAX MIN MAX MIN MAX MIN

Load Amps (FLA)

Full

XC20

Unit Dimensions -- Inches (mm)

35−1/2 (902)

2 (51)

39−3/8 (1000)

DISCHARGE AIR

LIQUID LINE CONNECTION

ELECTRICAL INLETS

SUCTION LINE CONNECTION

4−1/4(108)

4−3/4 (121)

SIDE VIEW

1 (25)

Model No.

XC20−024 39 991

XC20−036 39 991

XC20−048 45 1143

XC20−060 45 1143

END VIEW

in. mm

UNIT SUPPORT FEET

16−7/8

(429)

8−3/4 (222)

3−1/8

(79)

26−7/8

(683)

)3−3/4 (95

30−3/4 (781)

4−5/8 (117)

IMPORTANT

This unit must be matched with an indoor coil as specified in Lennox Product Specification bulletin. Coils previously charged with HCFC-22 must be flushed.

CAUTION

As with any mechanical equipment, contact with sharp sheet metal edges can result in personal injury. Take care while handling this equipment and use protective clothing.

BASE WITH ELONGATED LEGS

WARNING

Electric Shock Hazard. Can cause injury or death. Unit must be grounded in accordance with national and local codes. Line voltage is present at all components when unit is not in operation on units with single‐pole contactors. Disconnect all remote electric power supplies before opening access panel. Unit may have multiple power supplies.

WARNING

Electrical Hazard

High Voltage

Wait 5 Minutes

Electrical components may hold charge. Do not remove this panel or service this area for 5 minutes after the power has been removed.

XC20

Typical Unit Parts Arrangement

OUTDOOR

CONTROL

INVERTER REACTOR

CONTROL PANEL FOR

XC20-024 AND -036

DC INVERTER

CONTROL

GROUND LUG

CONTACTOR-SPST

OUTDOOR CONTROL

INVERTER REACTOR

CONTROL PANEL FOR

XC20-048 AND -060

DC INVERTER CONTROL

INVERTER NOISE FILTER

GROUND LUG

CONTACTOR-SPST

Figure 1. Control Panel Components

XC20

COMPRESSOR TOP CAP

SWITCH (THERMAL)

Typical Plumbing Components

COMPRESSOR

CRANKCASE HEATER THERMOSTAT (S40) OPENS AT 70ºF, CLOSES AT 50ºF

(ONE WAY - HFC-410A)

DRIER

LIQUID LINE SENSOR

SERVICE VALVE

Figure 2. Plumbing Component Locations

IMPORTANT

This unit must be matched with an indoor coil as specified in Lennox Product Specification bulletin. Coils previously charged with HCFC-22 must be flushed.

LOW PRESSURE

SWITCH

HIGH PRESSURE

SERVICE VALVE

SWITCH

CAUTION

As with any mechanical equipment, contact with sharp sheet metal edges can result in personal injury. Take care while handling this equipment and use protective clothing.

XC20

WARNING

Electric Shock Hazard. Can cause injury or death. Unit must be grounded in accordance with national and local codes.

Line voltage is present at all components when unit is not in operation on units with single‐pole contactors. Disconnect all remote electric power supplies before opening access panel. Unit may have multiple power supplies.

General

These instructions are intended as a general guide and do not supersede local codes in any way. Consult authorities who have jurisdiction before installation.

The XC20 is a high-efficiency residential split-system air conditioner, which features a variable-capacity scroll com pressor and uses HFC-410A refrigerant. Units are available in 2, 3, 4 and 5-ton sizes. The series is designed for use with an expansion valve (approved for use with HFC-410A) in the indoor unit only.

USING MANIFOLD GAUGE SET

When checking the system charge, only use a manifold gauge set that features low loss anti-blow back fittings.

Manifold gauge set used with HFC-410A refrigerant sys tems must be capable of handling higher system operating pressures. The gauges should be rated for use with pres sures of 0 - 800 psig on the high side and a low side of 30” vacuum to 250 psig, with dampened speed to 500 psi. Gauge hoses must be rated for use at or up to 800 psig of pressure with a 4000 psig burst rating.

Table 1. Torque Requirements

Parts Recommended Torque

Service valve cap 8 ft.- lb. 11 NM

Sheet metal screws 16 in.- lb. 2 NM

Machine screws #10 28 in.- lb. 3 NM

Compressor bolts 90 in.- lb. 10 NM

Gauge port seal cap 8 ft.- lb. 11 NM

TORQUE REQUIREMENTS

When servicing or repairing HVAC components, ensure the fasteners are appropriately tightened. Table 1 lists torque values for fasteners.

Operating Service Valves

The liquid and vapor line service valves are used for re moving refrigerant, flushing, leak testing, evacuating, checking charge and charging.

Each valve is equipped with a service port which has a fac tory-installed valve stem. Figure 3 provides information on how to access and operating both angle and ball service valves.

IMPORTANT

Only use hex wrenches of sufficient hardness (50Rc Rockwell Harness Scale minimum). Fully insert the wrench into the valve stem recess.

Service valve stems are factory-torqued (from 9 ft-lbs for small valves, to 25 ft-lbs for large valves) to prevent refrigerant loss during shipping and handling. Using a hex wrench rated at less than 50Rc risks rounding or breaking off the wrench, or stripping the valve stem recess.

See the Lennox Service and Application Note #C-08-1 for further details and information.

WARNING

The State of California has determined that this product may contain or produce a chemical or chemicals, in very low doses, which may cause serious illness or death. It may also cause cancer, birth defects, or reproductive harm.

IMPORTANT

To prevent stripping of the various caps used, the appropriately sized wrench should be used and fitted snugly over the cap before tightening.

XC20

SERVICE VALVES

ANGLE AND BALL

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.

SERVICE PORT CAP

SERVICE PORT CORE

(VALVE STEM SHOWN CLOSED) INSERT HEX WRENCH HERE

TO INDOOR

UNIT

(VALVE STEM SHOWN OPEN) INSERT HEX WRENCH HERE

STEM CAP

TO OUTDOOR UNIT

ANGLE-TYPE SERVICE VALVE

(BACK-SEATED OPENED)

When service valve is OPEN, the service port is open to line set, indoor and outdoor unit.

Operating Ball Type Service Valve:

1. Remove stem cap with an appropriately sized wrench.

2. Use an appropriately sized wrenched to open. To open valve, rotate stem counterclockwise 90°. To close, rotate stem clockwise 90°.

TO INDOOR UNIT

TO OPEN ROTATE STEM COUNTERCLOCKWISE 90°.

TO CLOSE ROTATE STEM CLOCKWISE 90°.

SERVICE PORT

CORE

CAP

TO OUTDOOR

UNIT

BALL (SHOWN CLOSED)

VALV E STEM

STEM CAP

ANGLE-TYPE SERVICE VALVE

(FRONT-SEATED CLOSED)

When service valve is CLOSED, the service port is open to the line set and indoor unit.

To Access Service Port:

A service port cap protects the service port core from contamination and serves as the primary leak seal.

1. Remove service port cap with an appropriately sized wrench.

2. Connect gauge set to service port.

3. When testing is completed, replace service port cap and tighten as follows:

D With torque wrench: Finger tighten and

torque cap per table 1.

D Without torque wrench: Finger tighten and

use an appropriately sized wrench to turn an additional 1/6 turn clockwise.

Reinstall Stem Cap:

Stem cap protects the valve stem from damage and serves as the primary seal. Replace the stem cap and tighten as follows:

D With Torque Wrench: Finger tighten and then

torque cap per table 1.

D Without Torque Wrench: Finger tighten and

use an appropriately sized wrench to turn an additional 1/12 turn clockwise.

1/6 TURN

1/12 TURN

NOTE - A label with specific torque requirements may be affixed to the stem cap. If the label is present, use the specified torque.

Figure 3. Angle and Ball-Type Service Valves

XC20

II. INSTALLATION

Unit Placement

CAUTION

This unit may weigh up to 320 lbs. It could take more than two people to lift this product. Take proper precautions when lifting heavy objects.

See Unit Dimensions on page 4 for sizing mounting slab, platforms or supports. Refer to figure 4 for mandatory installation clearance requirements.

POSITIONING CONSIDERATIONS

Consider the following when positioning the unit:

D Some localities are adopting sound ordinances based

on the unit sound level registered from the adjacent property, not from the installation property. Install the unit as far as possible from the property line.

D When possible, do not install the unit directly outside

a window. Glass has a very high level of sound trans mission. For proper placement of unit in relation to a window see figure 5, detail A.

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, de tail B.

NOTE - If necessary for stability, anchor unit to slab as de scribed in figure 5, detail D.

ELEVATING THE UNIT

Units are outfitted with elongated support feet as illustrated in figure 5, detail C.

If additional elevation is necessary, raise the unit by ex tending the height of the unit support feet. Use a 2-inch (50.8mm) Schedule 40 female threaded adapter to raise the height of the unit.

The specified coupling will fit snugly into the recessed por tion of the feet. Use additional 2-inch (50.8mm) Schedule 40 male threaded adaptors which can be threaded into the female threaded adaptors to make additional adjustments to the level of the unit.

NOTE - Keep the height of extenders short enough to en sure a sturdy installation. If it is necessary to extend the height further than what is stable, consider a different type of field-fabricated framework that is sturdy enough for greater heights.

NOTES:

Service clearance of 30 in. 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.

Clearance to one of the remaining two sides may be 12 in. and the final side may be 6 in.

A clearance of 24 in. must be maintained between two units.

48 in. clearance required on top of unit.

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 4. Installation Clearances

XC20

STABILIZING UNIT ON UNEVEN SURFACES

IMPORTANT

Unit Stabilizer Bracket Use (field-provided):

Always use stabilizers when unit is raised above the factory height. (Elevated units could become unstable in gusty wind conditions.)

Stabilizers may be used on factory height units when mounted on unstable an uneven surface.

1. Remove the louvered panel from each side to expose the unit base.

2. Install the brackets as illustrated in figure 5, detail D us ing conventional practices.

3. Replace the panels after installation is complete.

ROOF MOUNTING

Locate the unit above a load-bearing wall or area of the roof that can adequately support the unit. Consult local codes for rooftop applications.

NOTICE

Roof Damage! This system contains both refrigerant and oil. Some

rubber roofing material may absorb oil and cause the rubber to swell when it comes into contact with oil. The rubber will then bubble and could cause leaks. Protect the roof surface to avoid exposure to refrigerant and oil during service and installation. Failure to follow this notice could result in damage to roof surface.

XC20

DETAIL A DETAIL B

INSTALL UNIT LEVEL OR, IF ON A SLOPE, MAINTAIN SLOPE TOLERANCE OF 2 DEGREES (OR 2 INCHES PER 5 FEET [50 MM PER 1.5 M]) AWAY FROM BUILDING STRUCTURE.

Install unit away from windows.

TWO 90° ELBOWS INSTALLED IN LINE SET

WILL REDUCE LINE SET VIBRATION.

GROUND LEVEL

Slab Mounting at Ground Level

Outside Unit Placement

BUILDING

STRUCTURE

MOUNTING SLAB

DETAIL C

BASE

LEG DETAIL

2” (50.8MM) SCH 40

FEMALE THREADED

USE ADDITIONAL 2” SCH 40 MALE THREADED ADAPT ERS WHICH CAN BE THREADED INTO THE FEMALE THREADED ADAPTERS TO MAKE ADDITIONAL AD JUSTMENTS TO THE LEVEL OF THE UNIT.

Elevated Slab Mounting using Feet

ADAPTER

2” (50.8MM) SCH 40

MALE THREADED

ADAPTER

Extenders

DETAIL D

Slab Side Mounting

#10 1/2” LONG SELF-DRILLING

SHEET METAL SCREWS

STABILIZING BRACKET (18 GAUGE

METAL — 2” WIDTH; HEIGHT AS

#10 1-1/4” LONG HEX HEAD

SCREW AND FLAT WASHER

CONCRETE SLAB — USE TWO PLASTIC ANCHORS (HOLE DRILL 1/4”)

WOOD OR PLASTIC SLAB — NO PLASTIC ANCHOR (HOLE DRILL 1/8”)

REQUIRED)

CORNER POST

MINIMUM ONE

Deck Top Mounting

STABILIZING BRACKET (18 GAUGE METAL — 2” (50.8MM) WIDTH; HEIGHT AS REQUIRED); BEND TO FORM RIGHT ANGLE

SAME FASTENERS AS SLAB SIDE MOUNTING.

ONE BRACKET PER SIDE (MIN.); FOR EXTRA STABILITY, TWO BRACKETS PER SIDE, 2” (50.8MM) FROM EACH CORNER.

PER SIDE

FOR EXTRA

STABILITY

Stabilizing Unit on Uneven Surfaces

IMPORTANT - To help stabilize an outdoor unit, some installations may require strap

ping the unit to the pad using brackets and anchors commonly available in the marketplace.

COIL

BASE PAN

Figure 5. Placement and Slab Mounting

XC20

Removing and Installing Panels

LOUVERED PANEL REMOVAL

Remove the louvered panels as follows:

1. Remove two screws, allowing the panel to swing open slight ly.

2. Hold the panel firmly throughout this procedure. Rotate bot tom corner of panel away from hinged corner post until lower three tabs clear the slots as illustrated in Detail B.

3. Move panel down until lip of upper tab clears the top slot in corner post as illustrated in Detail A.

LOUVERED PANEL INSTALLATION

Position the panel almost parallel with the unit as illustrated in Detail D with the screw side as close to the unit as possible. Then, in a continuous motion:

1. Slightly rotate and guide the lip of the top tab inward as

illustrated in Detail A and C; then upward into the top slot of the hinge corner post.

2. Rotate the panel until it is completely vertical to fully en gage all of the tabs.

3. Holding the panel's hinged side firmly in place, close the right-hand side of the panel, aligning the screw holes.

4. When panel is correctly positioned and aligned, insert the screws and tighten.

IMPORTANT ALIGNMENT AND NOT DESIGNED TO SUPPORT WEIGHT OF PANEL.

PANEL SHOWN SLIGHTLY ROTATED TO ALLOW TOP TAB TO EXIT (OR ENTER) TOP SLOT FOR REMOVING (OR INSTALLING) PANEL.

! DO NOT ALLOW PANELS TO HANG ON UNIT BY TOP TAB. TAB IS FOR

SCREW

LIP

HOLES

Detail A

Detail B

ROTATE IN THIS DIRECTION;

ANGLE MAY BE TOO EXTREME

THEN DOWN TO REMOVE

SIDE TO MAINTAIN FULLY-ENGAGED TABS

PANEL

HOLD DOOR FIRMLY TO THE HINGED

Detail C

MAINTAIN MINIMUM PANEL ANGLE (AS CLOSE TO PARALLEL WITH THE UNIT AS POSSIBLE) WHILE INSTALLING PANEL.

Figure 6. Removing and Installing Panels

PREFERRED ANGLE FOR INSTALLATION

XC20

New or Replacement Line Set

REFRIGERANT LINE SET

This section provides information on installation or replace

ment of existing line set. If new or replacement line set is

not being installed then proceed to Brazing Connections on

page 16.

IMPORTANT

Lennox highly recommends changing line set when converting the existing system from HCFC-22 to HFC-410A If that is not possible and the line set is the proper size as referenced in table 2, use the procedure outlined under Flushing the System on page 19.

If refrigerant lines are routed through a wall, seal and isolate

the opening so vibration is not transmitted to the building.

Pay close attention to line set isolation during installation of

any HVAC system. When properly isolated from building

structures (walls, ceilings, floors), the refrigerant lines will

not create unnecessary vibration and subsequent sounds.

See figure 7 for recommended installation practices. Also,

consider the following when placing and installing a high-

efficiency outdoor unit.

Liquid lines that meter the refrigerant, such as RFC1 liquid

lines, must not be used in this application. Existing line set

of proper size may be reused. If system was previously

charged with HCFC-22 refrigerant, then existing line set

must be flushed (see Flushing the System on page 19).

IMPORTANT

Mineral oils are not compatible with HFC-410A. If oil

must be added, it must be a Polyol ester oil.

IMPORTANT !

If this unit is being matched with an approved line set or indoor unit coil that was previously charged with mineral oil, or if it is being matched with a coil which was manufactured before January of 1999, the coil and line set must be flushed prior to installation. Take care to empty all existing traps. Polyol ester (POE) oils are used in Lennox units charged with HFC-410A refrigerant. Residual mineral oil can act as an insulator, preventing proper heat transfer. It can also clog the expansion device and reduce system performance and capacity.

Failure to properly flush the system per the XC20 Installation and Service Procedures will void the warranty.

WARNING

Refrigerant can be harmful if it is inhaled. Refrigerant must be used and recovered responsibly.

Failure to follow this warning may result in personal injury or death.

WARNING

Fire, Explosion and Personal Safety Hazard. Failure to follow this warning could result in damage, personal inju ry or death.

Never use oxygen to pressurize or purge refrigeration lines. Oxygen, when exposed to a spark or open flame, can cause fire and/or an ex plosion, that could result in property damage, personal injury or death.

WARNING

When using a high pressure gas such as nitrogen to pressurize a refrigeration or air conditioning system, use a regulator that can control the pressure down to 1 or 2 psig (6.9 to 13.8 kPa).

Recommended POE oils are Mobil EAL ARCTIC 22 CC or

ICI EMKARATEt RL32CF.

WARNING

Danger of fire. Bleeding the refrigerant charge from only the high side may result in the low side shell and suction tubing being pressurized. Application of a brazing torch while pressurized may result in ignition of the refrigerant and oil mixture - check the high and low pressures before unbrazing.

IMPORTANT !

Some scroll compressors have an internal vacuum protector that will unload scrolls when suction pres sure 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 COMPRES SOR.

The XC20 is a variable-capacity cooling system utilizing variable-speed compressor technology. With the variablespeed compressor and variable pumping capacity, additional consideration must be given to refrigerant piping sizing and application. The following guidelines are to be used exclusively for the XC20 systems.

XC20

COOLING SYSTEM (HFC410A)

D Total equivalent length equals 180 feet (all piping and

fittings included).

NOTE - This is a general guide. Lengths may be more or less, depending on remaining system design factors.

D Maximum linear (actual) length = 150 feet. D Maximum linear liquid lift = 60 feet.

NOTE - Maximum lifts are dependent on total length, num ber of elbows, and other factors that contribute to total pressure drop.

D Maximum linear length of vapor riser = 60 feet. D Size vertical vapor riser per table 2. D Line set lengths up to 50 linear feet: Use rated line

sizes listed in table 2.

D Line set lengths between 51 and 150 linear feet:

Crankcase heater and nonbleed port TXV factory-in

stalled. No additional components required. Vertical vapor riser must be sized to the vapor riser listed in table 3 on systems with line sets longer than 51 feet. Use tables 3 and 4 to determine the correct liquid and vapor line sizes.

D Line set lengths over 150 linear feet: Not recom

mended.

D Additional oil is not required for systems with line

lengths up to 150 feet.

NOTE - Recommended POE oils are Mobil EAL ARCTIC 22 CC or ICI EMKARATEt RL32CF.

SUCTION TRAPS

In systems with the outdoor unit 5 to 60 feet above the in door unit, one trap must be installed at the bottom of the suction riser.

Table 2. Standard Refrigerant Line Set — Up to 50 Linear Feet

Valve Size Connections Recommended Line Sets

Model Number (-xx*)

XC20-024-230-XX 3/8” (10 mm) 3/4” (19 mm) L15-41-30 30 feet (9.1 m) 89J60

XC20-036-230-XX XC20-048-230-XX

XC20-060-230-XX 3/8” (10 mm) 1-1/8” (29 mm) ** Field-fabricated

* Applicable to all minor revision numbers unless otherwise specified. ** Some applications may require a field-provided 1-1/8” to 7/8” adapter.

Liquid Line Suction Line

3/8” (10 mm) 7/8” (22 mm)

L15 Line Set Model

L15-65-40 40 feet (12.2 m) 89J61

L15-65-50 50 feet (15.2 m) 89J62

Line Set Length

Catalog Number

Table 3. XC20 Line Set Guidelines — 51 to 150 Linear Feet in Length

Model

024 180 150 60 60 3/4” 5/8”

036 180 150 60 60 7/8” 3/4”

048 180 150 60 60 7/8” 7/8”

060 180 150 60 60 7/8” 7/8”

Maximum Total

Equivalent Length (ft)

Maximum Linear

(actual) Length (ft)

Maximum Vapor

Riser (ft)

Maximum

Linear Liquid

Lift (ft)

Preferred Vapor Line

Sizes for Horizontal

Runs

Required Vapor

Riser Size

Table 4. Liquid Line Diameter Selection Table

Total Linear Length (feet)

Unit

024

036

048

060

Line Size

5/16” 25 50 55 48 40 33

3/8” 25 50 60 60 60 60

3/8” 25 50 60 56 51 45

1/2” 25 50 60 60 60 60

3/8” 25 50 50 41 31 22

1/2” 25 50 60 60 60 60

3/8” 25 50 36 22 8 NR

1/2”

25 50 75 100 125 150

50 60 60 60 59

Note  Shaded rows indicate rated liquid line size.

1. Find your unit on the left side of the table.

2. Start with the rated liquid line size (shaded row) for the outdoor unit.

3. Select the actual total linear length of your system shown at the top of the table.

4. The elevation listed in the table is the maximum allowed for the liquid line listed.

5. Consider the larger liquid line size shown in the table if the elevation does not meet your requirements.

Max. Elevation

(ft)

XC20

LINE SET

INSTALLATION

LINE SET ISOLATION — THE FOLLOWING ILLUSTRATIONS ARE EXAM

PLES OF PROPER REFRIGERANT LINE SET ISOLATION:

REFRIGERANT LINE SET — TRANSITION

FROM VERTICAL TO HORIZONTAL

ANCHORED HEAVY NYLON WIRE TIE OR AUTOMOTIVE

MUFFLER‐TYPE HANGER

AUTOMOTIVE

MUFFLER‐TYPE HANGER

IMPORTANT - Refrigerant lines must not contact structure.

REFRIGERANT LINE SET — INSTALLING

VERTICAL RUNS (NEW CONSTRUCTION SHOWN)

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.

IMPORTANT - Refrigerant lines must not contact wall

OUTSIDE WALL

VAPOR LINE

LIQUID LINE

WALL STUD

STRAP LIQUID LINE TO VAPOR LINE

LIQUID LINE

NON-CORROSIVE

METAL SLEEVE

VAPOR LINE - WRAPPED IN ARMAFLEX

REFRIGERANT LINE SET — INSTALLING

HORIZONTAL RUNS

TO HANG LINE SET FROM JOIST OR RAFTER, USE EITHER METAL STRAPPING MATERIAL OR ANCHORED HEAVY NYLON WIRE TIES.

WIRE TIE (AROUND VAPOR LINE ONLY)

8 FEET (2.43 METERS)

STRAPPING

MATERIAL (AROUND

VAPOR LINE ONLY)

TAPE OR WIRE TIE

FLOOR JOIST OR

ROOF RAFTER

8 FEET (2.43 METERS)

NON-CORROSIVE METAL SLEEVE

STRAP THE VAPOR LINE TO THE JOIST OR RAFTER AT 8 FEET (2.43 METERS) INTERVALS THEN STRAP THE LIQUID LINE TO THE VAPOR LINE.

TAPE OR WIRE TIE

WIRE TIE

INSIDE WALL

WOOD BLOCK

BETWEEN

STUDS

SLEEVE

VAPOR LINE WRAPPED

WITH ARMAFLEX

OUTSIDE

WALL

PVC

PIPE

FIBERGLASS

INSULATION

NOTE - SIMILAR INSTALLATION PRACTICES SHOULD BE USED IF LINE SET IS TO BE INSTALLED ON EXTERIOR OF OUTSIDE WALL.

CAULK

STRAP

NON-CORROSIVE METAL SLEEVE

WIRE TIE

WOOD BLOCK

WIRE TIE

STRAP

LIQUID LINE

FLOOR JOIST OR

ROOF RAFTER

WARNING - 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.

Figure 7. Line Set Installation

XC20

Brazing Connections

Use the procedures outlined in figures 8 and 9 for brazing line set connections to service valves.

WARNING

IMPORTANT

Allow braze joint to cool before removing the wet rag from the service valve. Temperatures above 250ºF can damage valve seals.

Danger of fire. Bleeding the refrigerant charge from only the high side may result in pressurization of the low side shell and suction tubing. Application of a brazing torch to a pressurized system may result in ignition of the refrigerant and oil mixture

- Check the high and low pressures before applying heat.

CAUTION

Brazing alloys and flux contain materials which are hazardous to your health.

Avoid breathing vapors or fumes from brazing operations. Perform operations only in well-ventilated areas.

Wear gloves and protective goggles or face shield to protect against burns.

Wash hands with soap and water after handling brazing alloys and flux.

WARNING

Fire, Explosion and Personal Safety Hazard.

Failure to follow this warning could re sult in damage, personal injury or death.

Never use oxygen to pressurize or purge refrigeration lines. Oxygen, when exposed to a spark or open flame, can cause a fire and/or an explosion, that could result in property damage, per sonal injury or death.

XC20

PIPING PANEL REMOVAL AND LINE SET PREPARATION

Remove piping panel for easier access to service valves. 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.

CUT AND DEBUR

LINE SET SIZE MATCHES

SERVICE VALVE CONNECTION

SERVICE VALVE

COPPER TUBE

REDUCER

STUB

CONNECTION

LINE SET SIZE IS SMALLER

THAN CONNECTION

CAP AND CORE REMOVAL

Remove service cap and core from both the suction and liquid line

service ports.

SERVICE PORT CAP

SERVICE PORT CORE

LIQUID LINE SERVICE VALVE

REFRIGERANT LINE

DO NOT CRIMP SERVICE

VALVE CONNECTOR WHEN

PIPE IS SMALLER THAN

CONNECTION

ATTACH THE MANIFOLD GAUGE SET FOR BRAZING LIQUID AND SUCTION LINE SERVICE VALVES

A. Connect gauge set low pressure side to liquid line

service valve (service port).

B. Connect gauge set center port to bottle of nitrogen

with regulator.

C. With valve core removed from the suction line service

port, nitrogen flow will have an exit point.

SUCTION SERVICE PORT MUST BE OPEN AND

SERVICE PORT CORE REMOVED TO ALLOW

EXIT POINT FOR NITROGEN FLOW

SUCTION LINE

INDOOR

UNIT

SUCTION LINE

SERVICE VALVE

SUCTION LINE SERVICE

VALV E

LOW

ATTACH

GAUGES

OUTDOOR

UNIT

HIGH

SERVICE PORT CORE

SERVICE PORT CAP

LIQUID LINE

LIQUID LINE SERVICE

VALV E

Figure 8. Brazing Procedures

NITROGEN

XC20

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. See steps 3A, 3B and 3C on manifold gauge set connections.

BRAZE LINE SET

Wrap both service valves with water-saturated cloths as illustrated here and as mentioned in step 4, before brazing to line set. Cloths

must remain water-saturated throughout the brazing and cool-down process.

LIQUID LINE SERVICE VALVE

WHEN BRAZING LINE SET TO

SERVICE VALVES, POINT FLAME

AWAY FROM SERVICE VALVE.

IMPORTANT - Allow braze joint to cool. Apply additional

water-saturated cloths to help cool brazed joint. Do not remove water-saturated cloths until piping has cooled. Temperatures above 250ºF will damage valve seals.

LIQUID LINE

WATER-SATURATED CLOTH

WARNING

FIRE, PERSONAL INJURY, OR PROPERTY DAMAGE

may result if you do not wrap a water-saturated cloth around both liquid and suction line service valve bodies and copper tube stub while brazing the line set! The braze, when complete, must be quenched with water to absorb any residual heat.

Do not open service valves until refrigerant lines and indoor coil have been leak-tested and evacuated. Refer to Installation and Service Procedures manual found on DAVENET.

SUCTION LINE

PREPARATION FOR NEXT STEP

Disconnect manifold gauge set from service ports after all connections have been brazed. Apply additional water-saturated cloths to both

service valves to cool piping. Once piping is cool, remove all water-saturated cloths.

SUCTION LINE SERVICE

VALV E

SERVICE VALVES, POINT FLAME

WATER-SATURATED CLOTH

WHEN BRAZING LINE SET TO

AWAY FROM SERVICE VALVE.

Figure 9. Brazing Procedures (Continued)

XC20

Flushing the System

LINE SET AND INDOOR COIL (1 OF 2)

TYPICAL EXISTING EXPANSION VALVE REMOVAL PROCEDURE (UNCASED COIL

TWO PIECE PATCH PLATE

TYPICAL EXISTING FIXED ORIFICE REMOVAL PROCEDURE (UNCASED COIL

DISTRIBUTOR

ASSEMBLY

A. ON FULLY CASED COILS, REMOVE THE COIL ACCESS AND PLUMBING

PANELS.

B. REMOVE ANY SHIPPING CLAMPS HOLDING THE LIQUID LINE AND DIS

TRIBUTOR ASSEMBLY.

C. USING TWO WRENCHES, DISCONNECT LIQUID LINE FROM LIQUID LINE

ORIFICE HOUSING. TAKE CARE NOT TO TWIST OR DAMAGE DISTRIBU TOR TUBES DURING THIS PROCESS.

D. REMOVE AND DISCARD FIXED ORIFICE, VALVE STEM ASSEMBLY (IF

PRESENT) AND TEFLON

E. USE A FIELD-PROVIDED FITTING TO TEMPORARILY RECONNECT THE

LIQUID LINE TO THE INDOOR UNIT'S LIQUID LINE ORIFICE HOUSING.

SHOWN)

DISTRIBUTOR TUBES

REMOVE AND DISCARD

WHITE TEFLON

LIQUID LINE ORIFICE HOUSING

TEFLON® RING

FIXED ORIFICE

BRASS NUT

(IF PRESENT)

WASHER AS ILLUSTRATED ABOVE.

SEAL

LIQUID LINE ASSEMBLY

(INCLUDES STRAINER)

CONNECT GAUGES AND EQUIPMENT FOR FLUSHING PROCEDURE

INV ERT ED HCFC-22 CYLINDER CONTAINS CLE AN HCFC-22* TO BE USED FOR FLUSHING.

VAPOR LINE

SERVICE VALVE

EXISTING

INDOOR

UNIT

LIQUID LINE SERVICE

RECOVERY

CYLINDER

VALV E

VAPOR

LIQUID

NEW

OUTDOOR

UNIT

OPENED

A. INVERTED HCFC-22 CYLINDER WITH CLEAN REFRIGERANT* TO THE

VAPOR SERVICE VALVE.

B. HCFC-22 GAUGE SET (LOW SIDE) TO THE LIQUID LINE VALVE.

C. HCFC-22 GAUGE SET CENTER PORT TO INLET ON THE RECOVERY

MACHINE WITH AN EMPTY RECOVERY TANK TO THE GAUGE SET.

D. CONNECT RECOVERY TANK TO RECOVERY MACHINE PER MACHINE

INSTRUCTIONS.

*IMPORTANT - Clean refrigerant is any refrigerant in a system that has not had compressor burn out. If the system has experienced burn out, it is recommended that the existing line set and indoor coil be replaced.

RECOVERY MACHINE

MANIFOLD

LOW

TANK RETURN

INLET

DISCHARGE

GAUGE

CLOSED

(UNCASED COIL ONLY)

HIGH

SHOWN)

LIQUID LINE

DISTRIBUTOR

TUBES

DISTRIBUTOR

ASSEMBLY

MALE EQUALIZER

LINE FITTING

SENSING BULB

A. ON FULLY CASED COILS, REMOVE THE COIL ACCESS AND PLUMBING

PANELS.

B. REMOVE ANY SHIPPING CLAMPS HOLDING THE LIQUID LINE AND DIS

TRIBUTOR ASSEMBLY.

C. DISCONNECT THE EQUALIZER LINE FROM THE CHECK EXPANSION

VALVE EQUALIZER LINE FITTING ON THE VAPOR LINE.

D. REMOVE THE VAPOR LINE SENSING BULB.

E. DISCONNECT THE LIQUID LINE FROM THE CHECK EXPANSION VALVE

AT THE LIQUID LINE ASSEMBLY.

F. DISCONNECT THE CHECK EXPANSION VALVE FROM THE LIQUID LINE

ORIFICE HOUSING. DO NOT TO TWIST OR DAMAGE DISTRIBUTOR TUBES DURING THIS PROCESS.

G. REMOVE AND DISCARD CHECK EXPANSION VALVE AND THE TWO TEF

H. USE A FIELD-PROVIDED FITTING TO TEMPORARILY RECONNECT THE

RINGS.

LON

LIQUID LINE TO THE INDOOR UNIT'S LIQUID LINE ORIFICE HOUSING.

ORIFICE

HOUSING

EQUALIZER LINE

STUB END

TEFLON RING

VAPOR

CHECK

EXPANSION

VALV E

LIQUID LINE

ASSEMBLY WITH

BRASS NUT

LINE

TEFLON

RING

FLUSHING LINE SET

CAUTION -This procedure should not be performed on systems

which contain contaminants (Example, compressor burn out).

THE LINE SET AND INDOOR UNIT COIL MUST BE FLUSHED WITH AT LEAST THE SAME AMOUNT OF CLEAN REFRIGERANT* THAT PRE VIOUSLY CHARGED THE SYSTEM. CHECK THE CHARGE IN THE FLUSHING CYLINDER BEFORE PROCEEDING.

A. SET THE RECOVERY MACHINE FOR LIQUID RECOVERY AND

START THE RECOVERY MACHINE. OPEN THE GAUGE SET VALVES TO ALLOW THE RECOVERY MACHINE TO PULL A VACU UM ON THE EXISTING SYSTEM LINE SET AND INDOOR UNIT COIL.

B. INVERT THE CYLINDER OF CLEAN HCFC-22* AND OPEN ITS

VALVE TO ALLOW LIQUID REFRIGERANT TO FLOW INTO THE SYS TEM THROUGH THE VAPOR LINE VALVE. ALLOW THE REFRIGER ANT TO PASS FROM THE CYLINDER AND THROUGH THE LINE SET AND THE INDOOR UNIT COIL BEFORE IT ENTERS THE RECOVERY MACHINE.

C. AFTER ALL OF THE LIQUID REFRIGERANT HAS BEEN RECOV

ERED, SWITCH THE RECOVERY MACHINE TO VAPOR RECOVERY SO THAT ALL OF THE HCFC-22 VAPOR IS RECOVERED. ALLOW THE RECOVERY MACHINE TO PULL SYSTEM DOWN TO 0.

D. CLOSE THE VALVE ON THE INVERTED HCFC-22 DRUM AND THE

GAUGE SET VALVES. PUMP THE REMAINING REFRIGERANT OUT OF THE RECOVERY MACHINE AND TURN OFF THE MACHINE.

SENSING

LINE

LIQUID

LINE

XC20

FLUSHING LINE SET AND INDOOR COIL (2 OF 2)

TYPICAL NEW CHECK EXPANSION VALVE INSTALLATION PROCEDURE

THIS OUTDOOR UNIT IS DESIGNED FOR USE IN SYSTEMS THAT USE A CHECK EXPANSION VALVE METERING DEVICE. SEE LENNOX XC20 PRODUCT SPECIFICATIONS FOR APPROVED EXPANSION VALVE KIT MATCH-UPS AND APPLICATION INFORMATION.

THE EXPANSION VALVE UNIT CAN BE INSTALLED INTERNAL OR EXTERNAL TO THE INDOOR COIL. IN APPLICATIONS WHERE AN

TWO PIECE

PATCH PLATE

(UNCASED

COIL ONLY)

DISTRIBUTOR

TUBES

DISTRIBUTOR

ASSEMBLY

MALE EQUALIZER LINE

FITTING (SEE

EQUALIZER LINE INSTALLATION FOR FURTHER DETAILS)

SENSING BULB INSULATION IS REQUIRED IF MOUNTED EXTERNAL TO THE COIL CASING. SEE SENSING BULB INSTALLATION FOR BULB POSITIONING.

(Uncased Coil Shown)

LIQUID LINE

ORIFICE

HOUSING

STUB

END

TEFLON RING

EQUALIZER LINE

EXPANSION

VALV E

LIQUID LINE

ASSEMBLY WITH

BRASS NUT

VAPOR

LINE

UNCASED COIL IS BEING INSTALLED IN A FIELD-PROVIDED PLENUM, INSTALL THE CHECK EXPANSION VALVE IN A MANNER THAT WILL PROVIDE ACCESS FOR FIELD SERVICING OF THE EXPANSION VALVE. REFER TO BELOW ILLUSTRATION FOR REFERENCE DURING INSTALLATION OF EXPANSION VALVE UNIT.

TEFLON

RING

A. REMOVE THE FIELD-PROVIDED FITTING THAT TEMPORARILY RECON

NECTED THE LIQUID LINE TO THE INDOOR UNIT'S DISTRIBUTOR AS

SENSING

LINE

LIQUID LINE

SEMBLY.

B. INSTALL ONE OF THE PROVIDED TEFLON

STUBBED END OF THE EXPANSION VALVE AND LIGHTLY LUBRICATE THE CONNECTOR THREADS AND EXPOSE SURFACE OF THE TEFLON RING WITH REFRIGERANT OIL.

C. ATTACH THE STUBBED END OF THE EXPANSION VALVE TO THE LIQUID

LINE ORIFICE HOUSING. FINGER TIGHTEN AND USE AN APPROPRIATELY SIZED WRENCH TO TURN AN ADDITIONAL 1/2 TURN CLOCKWISE AS IL LUSTRATED IN THE FIGURE ABOVE, OR 20 FT-LB.

D. PLACE THE REMAINING TEFLON

OF THE EXPANSION VALVE. LIGHTLY LUBRICATE CONNECTOR THREADS AND EXPOSE SURFACE OF THE TEFLON FRIGERANT OIL.

E. ATTACH THE LIQUID LINE ASSEMBLY TO THE EXPANSION VALVE. FIN

GER TIGHTEN AND USE AN APPROPRIATELY SIZED WRENCH TO TURN AN ADDITIONAL 1/2 TURN CLOCKWISE AS ILLUSTRATED IN THE FIGURE ABOVE OR 20 FT-LB.

9 O'CLOCK TO

3 O'CLOCK

BULB

WASHER AROUND THE OTHER END

RINGS AROUND THE

ON LINES SMALLER THAN 7/8”, MOUNT SENSING BULB BETWEEN THE 9 AND 3 O'CLOCK POSITIONS.

SENSING BULB INSTALLATION

VAPOR LINE

A. ATTACH THE VAPOR LINE SENSING BULB IN THE PROPER

ORIENTATION AS ILLUSTRATED TO THE RIGHT USING THE CLAMP AND SCREWS PROVIDED.

NOTE - CONFIRM PROPER THERMAL CONTACT BETWEEN VAPOR LINE AND CHECK EXPANSION BULB BEFORE INSU LATING THE SENSING BULB ONCE INSTALLED.

B. CONNECT THE EQUALIZER LINE

FROM THE EXPANSION VALVE TO THE EQUALIZER VAPOR PORT ON THE VAPOR LINE. FINGER TIGHTEN THE FLARE NUT PLUS 1/8 TURN (7 FT-LBS) AS ILLUS TRATED BELOW.

1/8 TURN

VAPOR LINE

BULB

FLARE SEAL CAP

ON 7/8” AND LARGER LINES, MOUNT SENSING BULB AT EITHER THE 4 OR 8 O'CLOCK POSITION. NEVER MOUNT

BULB

NOTE - NEVER MOUNT THE SENSING BULB ON

BOTTOM OF LINE.

THE SENSING BULB ON BOTTOM OF LINE.

FLARE NUT

1/2 TURN

RING WITH RE

EQUALIZER LINE INSTALLATION

REMOVE AND DISCARD EITHER THE FLARE SEAL CAP OR FLARE NUT WITH COPPER FLARE SEAL BONNET FROM THE EQUALIZER LINE PORT ON THE VAPOR LINE AS ILLUSTRATED IN THE FIGURE TO THE RIGHT.

XC20

COPPER FLARE SEAL BONNET

MALE BRASS EQUALIZER LINE FITTING

VAPOR LINE

IMPORTANT

Leak Testing the System

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.

IMPORTANT

If this unit is being matched with an approved line set or indoor unit coil which was previously charged with mineral oil, or if it is being matched with a coil which was manufactured before January of 1999, the coil and line set must be flushed prior to installation. Take care to empty all existing traps. Polyol ester (POE) oils are used in Lennox units charged with HFC-410A refrigerant. Residual mineral oil can act as an insulator, preventing proper heat transfer. It can also clog the expansion device, and reduce the system performance and capacity. Failure to properly flush the system per the instructions below will void the warranty.

IMPORTANT

Leak detector must be capable of sensing HFC refrigerant.

WARNING

Refrigerant can be harmful if it is inhaled. Refrigerant must be used and recovered responsibly.

Failure to follow this warning may result in personal injury or death.

XC20

LEAK TEST

LINE SET AND INDOOR COIL

NOTE - NORMALLY, THE HIGH PRESSURE HOSE IS CONNECTED TO THE LIQUID LINE PORT. HOWEVER, CONNECTING IT TO THE VAPOR PORT BETTER PROTECTS THE MANIFOLD GAUGE SET FROM HIGH PRESSURE DAMAGE.

LOW

HIGH

CONNECT GAUGE SET

A. CONNECT AN HFC-410A MANIFOLD GAUGE SET HIGH PRESSURE

HOSE TO THE VAPOR VALVE SERVICE PORT.

B. WITH BOTH MANIFOLD VALVES CLOSED, CONNECT THE CYLINDER

OF HFC-410A REFRIGERANT TO THE CENTER PORT OF THE MANIFOLD GAUGE SET.

NOTE - LATER IN THE PROCEDURE, THE HFC-410A CONTAINER WILL BE REPLACED BY THE NITROGEN CONTAINER.

NITROGEN

TEST FOR LEAKS

AFTER THE LINE SET HAS BEEN CONNECTED TO THE INDOOR AND OUTDOOR UNITS, CHECK THE LINE SET CON NECTIONS AND INDOOR UNIT FOR LEAKS. USE THE FOLLOWING PROCEDURE TO TEST FOR LEAKS:

A. WITH BOTH MANIFOLD VALVES CLOSED, CONNECT THE CYLINDER OF HFC-410A REFRIGERANT TO THE CENTER PORT OF THE

MANIFOLD GAUGE SET. OPEN THE VALVE ON THE HFC-410A CYLINDER (VAPOR ONLY).

B. OPEN THE HIGH PRESSURE SIDE OF THE MANIFOLD TO ALLOW HFC-410A INTO THE LINE SET AND INDOOR UNIT. WEIGH IN A TRACE

AMOUNT OF HFC-410A [A TRACE AMOUNT IS A MAXIMUM OF TWO OUNCES (57 G) REFRIGERANT OR THREE POUNDS (31 KPA) PRES SURE]. CLOSE THE VALVE ON THE HFC-410A CYLINDER AND THE VALVE ON THE HIGH PRESSURE SIDE OF THE MANIFOLD GAUGE SET. DISCONNECT THE HFC-410A CYLINDER.

C. CONNECT A CYLINDER OF DRY NITROGEN WITH A PRESSURE REGULATING VALVE TO THE CENTER PORT OF THE MANIFOLD

GAUGE SET.

D. ADJUST DRY NITROGEN PRESSURE TO 150 PSIG (1034 KPA). OPEN THE VALVE ON THE HIGH SIDE OF THE MANIFOLD GAUGE SET IN

ORDER TO PRESSURIZE THE LINE SET AND THE INDOOR UNIT.

E. AFTER A FEW MINUTES, OPEN ONE OF THE SERVICE VALVE PORTS AND VERIFY THAT THE REFRIGERANT ADDED TO THE SYSTEM

EARLIER IS MEASURABLE WITH A LEAK DETECTOR.

F. AFTER LEAK TESTING, DISCONNECT GAUGES FROM SERVICE PORTS.

HFC-410A

MANIFOLD GAUGE SET

TO VAPOR

SERVICE VALVE

OUTDOOR UNIT

XC20

Figure 10. System Leak Test

Evacuating the System

LINE SET AND INDOOR COIL

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 VAPOR LINE SERVICE VALVE.

B. CONNECT HIGH SIDE OF MANIFOLD

GAUGE SET TO LIQUID LINE SERVICE VALVE.

C. CONNECT MICRON GAUGE TO AN

AVAILABLE CONNECTOR ON THE 1/4 SAE IN-LINE TEE.

D. CONNECT THE VACUUM PUMP (WITH

VACUUM GAUGE) TO THE CENTER PORT OF THE MANIFOLD GAUGE SET. THE CENTER PORT LINE IS USED LATER FOR BOTH THE AND NITROGEN CONTAINERS.

OUTDOOR

UNIT

A34000 1/4 SAE TEE WITH SWIVEL COUPLER

500

MICRON

GAUGE

LOW

TO VAPOR

SERVICE VALVE

MANIFOLD

GAUGE SET

HIGH

HFC-410A

VACUUM PUMP

TO LIQUID LINE SERVICE VALVE

NITROGEN

EVACUATE THE SYSTEM

A. OPEN BOTH MANIFOLD VALVES AND START THE VACUUM PUMP.

B. EVACUATE THE LINE SET AND INDOOR UNIT TO AN ABSOLUTE PRESSURE OF 23,000 MICRONS (29.01 INCHES OF MERCURY).

NOTE - DURING THE EARLY STAGES OF EVACUATION, IT IS DESIRABLE TO CLOSE THE MANIFOLD GAUGE VALVE AT LEAST ONCE. A RAPID RISE IN PRESSURE INDICATES A RELATIVELY LARGE LEAK. IF THIS OCCURS, REPEAT THE LEAK TESTING PROCEDURE.

NOTE - THE TERM ABSOLUTE PRESSURE REFERS TO THE TOTAL ACTUAL PRESSURE (ABOVE ABSOLUTE ZERO) WITHIN A GIVEN VOLUME OR SYSTEM. ABSOLUTE PRESSURE IN A VACUUM IS EQUAL TO ATMOSPHERIC PRESSURE MINUS VACUUM PRESSURE.

C. WHEN THE ABSOLUTE PRESSURE REACHES 23,000 MICRONS (29.01 INCHES OF MERCURY), CLOSE THE MANIFOLD GAUGE VALVES, TURN

OFF THE VACUUM PUMP AND DISCONNECT THE MANIFOLD GAUGE CENTER PORT HOSE FROM VACUUM PUMP. ATTACH THE MANIFOLD CENTER PORT HOSE TO A DRY NITROGEN CYLINDER WITH PRESSURE REGULATOR SET TO 150 PSIG (1034 KPA) AND PURGE THE HOSE. OPEN THE MANIFOLD GAUGE VALVES TO BREAK THE VACUUM IN THE LINE SET AND INDOOR UNIT. CLOSE THE MANIFOLD GAUGE VALVES.

D. SHUT OFF THE DRY NITROGEN CYLINDER AND REMOVE THE MANIFOLD GAUGE HOSE FROM THE CYLINDER. OPEN THE MANIFOLD

GAUGE VALVES TO RELEASE THE DRY NITROGEN FROM THE LINE SET AND INDOOR UNIT.

E. RECONNECT THE MANIFOLD GAUGE TO THE VACUUM PUMP, TURN THE PUMP ON, AND CONTINUE TO EVACUATE THE LINE SET AND IN

DOOR UNIT UNTIL THE ABSOLUTE PRESSURE DOES NOT RISE ABOVE 500 MICRONS (29.9 INCHES OF MERCURY) WITHIN A 20-MINUTE PERIOD AFTER SHUTTING OFF THE VACUUM PUMP AND CLOSING THE MANIFOLD GAUGE VALVES.

F. WHEN THE ABSOLUTE PRESSURE REQUIREMENT ABOVE HAS BEEN MET, DISCONNECT THE MANIFOLD HOSE FROM THE VACUUM PUMP

AND CONNECT IT TO AN UPRIGHT CYLINDER OF HFC-410A REFRIGERANT. OPEN THE MANIFOLD GAUGE VALVE 1 TO 2 PSIG IN ORDER TO RELEASE THE VACUUM IN THE LINE SET AND INDOOR UNIT.

G. PERFORM THE FOLLOWING:

1. Close manifold gauge valves.

. Shut off HFC-410A cylinder. . Reinstall service valve cores by removing manifold hose from service valve. Quickly install cores with core

tool while maintaining a positive system pressure.

. Replace the stem caps and secure finger tight, then tighten an additional one-sixth (1/6) of a turn as illus

trated.

RECOMMEND

MINIMUM 3/8” HOSE

1/6 TURN

Figure 11. Evacuating System

XC20

IMPORTANT

Load Shedding

Use a thermocouple or thermistor electronic vacuum gauge that is calibrated in microns. Use an instrument capable of accurately measuring down to 50 microns.

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.

Evacuating the system of non-condensables is critical for proper operation of the unit. Non-condensables are defined as any gas that will not condense under temperat ures and pressures present during operation of an air conditioning system. Non-condensables combine with re frigerant to produce substances that corrode copper piping and compressor parts.

Electrical

In the U.S.A., wiring must conform with current local codes and the current National Electric Code (NEC). In Canada, wiring must conform with current local codes and the current Canadian Electrical Code (CEC).

Refer to the furnace or air handler installation instructions for additional wiring application diagrams. Refer to unit nameplate for minimum circuit ampacity and maximum over-current protection size.

24VAC TRANSFORMER

Use the transformer provided with the furnace or air hand ler for low‐voltage control power (24VAC - 40 VA minimum).

Utility Load Shedding Mode ACTIVATED (Utility Cycled Unit OFF) – The normally closed set of

contacts in the utility load shedding control receiver OPEN. This removes 24VAC from the coil of the field-provided re lay (catalog # 69J79). The relay contacts close (terminal 7 to terminal 2), completing the circuit between terminals R and L on the outdoor control. The 24VAC input to terminal L activates the load-shedding mode in the outdoor control, cycling the outdoor unit OFF. The 7-Segment display on the outdoor control displays a load shedding alert code (E600) and an alert appears on the display of the iComfort

thermostat. The customer receives email notifica

Wi-Fi tions when the alert occurs, if the option to receive notifications is selected.

Utility Load-Shedding Mode DEACTIVATED (Normal Equipment Operation) – When load shedding

mode is not required, the contacts in the utility load control receiver are closed. This provides 24VAC to the coil of the field-provided relay (catalog # 69J79).The relay contacts

OPEN (terminal 7 to terminal 2) removing 24VAC from the L terminal on the outdoor control. This deactivates the

load-shedding mode in the outdoor control. The outdoor unit returns to normal operation and alert code clears once load-shedding mode is deactivated.

For more information, see the Load-Shedding Feature Wir ing Diagram on page 47.

SIZE CIRCUIT AND INSTALL DISCONNECT SWITCH

REFER TO THE UNIT NAMEPLATE FOR MINIMUM CIRCUIT AMPACITY, AND MAXIMUM FUSE OR CIRCUIT BREAKER (HACR PER NEC). INSTALL POWER WIRING AND PROPERLY SIZED DISCONNECT SWITCH.

MAIN FUSE BOX/ BREAKER PANEL

DISCONNECT

SWITCH

NOTE - UNITS ARE APPROVED FOR USE ONLY WITH COPPER CONDUCTORS. GROUND UNIT AT DISCONNECT SWITCH OR TO AN EARTH GROUND.

Figure 12. Electrical Installation

INSTALL THERMOSTAT

INSTALL ROOM THERMOSTAT (ORDERED SEPARATELY) ON AN INSIDE WALL, APPROXIMATELY IN THE CENTER OF THE

CONDITIONED AREA AND 5 FEET (1.5M) FROM THE FLOOR. IT SHOULD NOT BE INSTALLED ON AN OUTSIDE WALL OR WHERE IT CAN BE AFFECTED BY SUNLIGHT OR DRAFTS.

THERMOSTAT

5 FEET

(1.5M)

NOTE - 24VAC, CLASS II CIRCUIT CONNECTIONS ARE MADE IN THE CON TROL BOX.

XC20

+ 54 hidden pages

Lennox XC20-036-230-01, XC20-060-230-01, XC20-024-230-01, XC20-048-230-01 Installation And Service Procedure

Specifications and Main Features

Frequently Asked Questions

User Manual