Lennox Harmony III, Installation, Setup And User Manual

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allows conditioning of different zones within a residence while using a single HVAC
system. The zone control system operates in two modes: central control (vacation
mode) or zone control. LEDs on the zone control panel indicate the current
operating mode.
When the system is in the central control mode, a demand from the central control
thermostat results in conditioned air being directed to all of the zones. In this mode,
zone 1 thermostat is designated as the controlling thermostat; other thermostats
are not used. When the system is in the zone control mode, a zone is conditioned
only upon demand from that zone’s thermostat. The zone control system is ideal for
retrofit applications as well as new construction. The system controls the air volume,
eliminating the need for bypass dampers in most applications. The homeowner
controls the system using zone thermostats to make comfort settings for each
zone. A programmable thermostat should be used to provide a specialized heating
and cooling sequence. While the system is in the zone mode, a programmable
thermostat controls the temperature for its particular zone.
1.5. Residential Zone Control System - Overview of Field
Wiring
VARIABLE SPEED
FURNACE OR AIR
HANDLER
ZONE 1 ZONE 2
*ZONE 4
POWER
THERMOSTAT (ZONE 1 OR CENTRAL CONTROL
THERMOSTAT WHEN IN VACATION MODE)
ZONE DAMPER
THERMOSTAT
(ZONE)
CONDENSING
UNIT OR HEAT
DOOR UNIT
TRANSFORMER TO POWER
MOSTATS AND DAMPERS;
ALSO POWERS HZA CONTROL
WHEN EDA IS USED)
THERMOSTAT
(ZONE)
LEGEND -
A Five wire low voltage — 18 ga. minimum
B
Two wire low voltage OR Three wire if Power-open, Power-closed — 18 ga. minimum
C INDOOR UNIT: Up to nine wire low voltage — 18 ga. minimum
D OUTDOOR UNIT:
- Two (3, if LSOM equipped unit) wire low voltage (single
‐
stage condensing unit or EDA) 18 ga. minimum
- Three (4, if LSOM equipped unit) wire low voltage (two
‐
stage condensing unit) 18 ga. minimum
- Up to seven wire low voltage (single
‐
stage heat pump outdoor unit) 18 ga. minimum
- Up to eight wire low voltage (two
‐
stage heat pump outdoor unit) 18 ga. minimum
E Two wire low voltage (discharge air sensor) 18 ga. minimum
F
Two wire low voltage (pressure switch, heat pump only) — 18 ga. minimum
G Two wire — 18 ga. minimum
H Refer to the Humiditrol® Zoning Accessory (HZA) for wiring requirements.
*NOTE - Zone 3 and zone 4 not available with single
‐
stage outdoor unit.
OUTDOOR
THERMOSTAT /
BALANCE
POINT SENSOR
ZONE CONTROL
SYSTEM PANEL
A
B
DISCHARGE
AIR SENSOR
E
C
D
F
ZONE DAMPER
G
*ZONE 3
THERMOSTAT
(ZONE)
ZONE DAMPER
ZONE DAMPER
HUMIDITROL
®
ENHANCED
DEHUMIDIFICATION
ACCESSORY
HUMIDITROL ®
ZONING
ACCESSORY (HZA)
OPTIONAL
H
A
B
B
A
B
A
B
Figure 1. Field Wiring
1.6. System Components
The Harmony III zoning system consists of the following (required):
• Harmony III zoning system zone control panel (included)
• Discharge Air sensor (included)
• Thermostats (one for each zone; ordered separately)
• 24VAC Power Transformer(s) (ordered separately)
• Dampers (ordered separately)
• Pressure Switch and Tee with Schrader valve (for Heat Pump systems; ordered
separately)
• Balance Point Sensor (Optional for Dual Fuel systems)
• Defrost Tempering Kit (Optional for Dual Fuel systems)
• Remote Vacation Switch (optional; ordered separately)
1.6.1. Zone Control System
The Harmony III zoning system monitors electrical signals and directs control
signals between thermostats, dampers, and HVAC equipment.
JUMPERS:
STAGING
TEMP`
HEATING--
COOLING--
AIR
REDUCTION
CONT.--
HEATING--
EQUIPMENT
CONNECTIONS
THERMOSTAT
CONNECTIONS
24VAC
CONNECTIONS
PIAB
JUMPERS
SYS CONFIG AND
E-HEAT JUMPERS
DIAGNOSTIC
LEDS
TIME
DELAY
RIDE
FAULT
RECALL
OUTDOOR THERMOSTAT /
BALANCE POINT SENSOR
CONNECTIONS
PRESSURE
NECTIONS
DISCHARGE
AIR SENSOR
CONNECTIONS
DAMPER
TIONS
FUSES
SYSTEM OPERATION LEDS
REMOTE
VACATION
SWITCH;
CONNECTIONS
FOR HZA
Figure 2. Harmony III Zoning System Zone Control Panel