Lennox CHP20-060

Page 1
 2001 Lennox Industries Inc.
Litho U.S.A.
Corp. 0109-L2
Service Literature
CHA/CHP16
CHP20
2 to 5 ton (7.0 to 17.6 kW)
CHA/CHP16, CHP20 SERIES UNITS
CHA/CHP16 and CHP20 series units in the 2 through 5 ton
(7.0 through 17.6 kW) sizes are designed for outdoor roofĆ
top or ground level installations in light commercial applicaĆ
tions. Electric heat is available in several kW sizes. Models
are available in single or three phase power supply and can
be utilized in downflow or horizontal supply and return air.
CHA/CHP16-024/030 model units are equipped with a
reciprocating compressor. CHA/CHP16-036/060 and
CHP20-024/060 model units are equipped with scroll
compressors. The scroll compressor offers high voluĆ
metric efficiency, quiet operation and the ability to start
under system load. Continuous flank contact, mainĆ
tained by centrifugal force, minimizes gas leakage and
maximizes efficiency. The motor is internally protected
from excessive current and temperature.
CHA/CHP16 and CHP20 model units are designed to acĆ
cept any of several different thermostat control systems
with minimum field wiring. Control options such as econĆ
omizer, warm up kit, Honeywell T7300 thermostat or
Honeywell T8600/T8611/T8621 thermostat controls
connect to the unit with jackĆplugs. When plugged in the
controls become an integral part of the unit wiring. Low
voltage thermostat connections facilitate thermostat
field wiring.
Optional electric heat is field installed. Electric heat operĆ
ates in single or multiple stages depending on the kW size.
5kW through 25 kW sizes are available for the CHA/CHP16
and CHP20 units.
Information in this manual is for use by a qualified service
technicial only. All specifications in this manual are subject
to change. Procedures outlined in this manual are repesĆ
ented as a recommendation only and do not supersede or
replace state or local codes.
IMPORTANT
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, personĆ
al injury or loss of life. Installation and service must
be performed by a qualified installer, service agency
or the gas supplier.
WARNING
Electric shock hazard. Can cause injury
or death. Before attempting to perform
any service or maintenance, turn the
electrical power to unit OFF at disconĆ
nect switch(es). Unit may have multiple
power supplies.
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.

Lennox CHP20-060 Specifications

General

SEER	20
Refrigerant	R-410A
Voltage	208/230V
Phase	1
Cooling Capacity	59000 BTU
Stages	Variable

Summary

General Unit Information

Important Safety Warnings

Critical safety warnings regarding installation, service, electrical shock, and refrigerant handling.

Electrostatic Discharge (ESD) Precautions

ESD Handling Precautions

Precautions for handling electronic components to prevent damage from electrostatic discharge.

CHA16 Specifications

CHP16 Specifications

CHP20 Specifications

Cooling Specifications

Tonnage, cooling capacity in Btuh (kW), and ARI certified performance ratings.

Heating Ratings

Electrical and Heat Specifications

Optional Accessories CHACHP16

Economizers

Description of REMD16 downflow and EMDH16 horizontal economizers.

Electric Heat and Controls

Optional Accessories CHP20

Economizers and Controls

Description of economizer systems and enthalpy control.

Electric Heat and Other Accessories

Electrical Data CHP16

Single Phase Electrical Data

Electrical specifications for single-phase CHA16 units.

Three Phase Electrical Data

Electrical specifications for three-phase CHA16 units.

Unit Components (Continued)

Defrost Control CMC1

Operation and function of the solid-state defrost control.

Scroll Compressor Description

Cutaway Diagram and Operation

Explanation of scroll compressor mechanics and gas compression.

Scroll Compressor Properties

Compressor Head Caution

Warning about potential hot compressor heads causing burns.

Scroll Compressor Operation and Components

Scroll Compressor Mechanics

Safety Switches and Reversing Valve

Function of freezestat, high pressure switches, and reversing valve.

Optional Electric Heat (ECH16)

Matchups and Ratings

Compatibility and electrical ratings for ECH16 electric heat.

Optional Electric Heat (ECH16) (Continued)

Heat Relays, Fuses, and Limits

Placement and Installation, Electrical, and Start-Up

Installation Requirements

General installation guidelines, codes, and roof mounting frame usage.

Electrical Connections and Power Supply

Details on field wiring, power supply, and voltage requirements.

Start-Up and Preliminary Checks

Procedures for initial unit startup, crankcase heaters, and pre-checks.

Cooling System Service Checks

Refrigerant Safety Precautions

Important safety warnings regarding refrigerant handling.

Gauge Manifold Attachment and Cooling Start-Up

Compressor Rotation and Charging

Ensuring correct compressor rotation and refrigerant charging procedures.

Heating System Service Checks and Blower Operation

Heating System Service Checks

Indoor Blower Operation and Adjustment

Minimum Blower Speed and Maintenance

Maintenance Safety Caution

Warning regarding personal injury during maintenance operations.

Accessories (Continued)

Economizer Controls and Operation

Enthalpy control, sensors, minimum positioner, and operating examples.

Economizer Operation Details

Enthalpy control setpoint adjustment and operational scenarios.

Economizer Control Adjustments

Low Ambient Kit and Roof Curb Kit

Wiring Diagrams and Operation Sequence

CHP1620 P Voltage Wiring Diagram

Schematic diagram for P voltage units.

Sequence of Operation (P Voltage)

Detailed steps for cooling, heating, and defrost operation.

Electric Heat Sequence of Operation

Call for Heat Conditions

Heat Stage Operation

Steps for energizing and de-energizing heating elements.

Electromechanical Thermostat with Economizer

Wiring Diagram

Operation Sequences

How the thermostat and economizer interact during cooling modes.