White Rodgers 21D83M-843 Specification

Single-Stage/HSI Integrated
Furnace Control Kit

OEM Replacement

21D83M-843

Nitride Ignition
Integrated Furnace Control

Controls Gas Valve, Ignitor, Blower, Inducer,
Humidifier and Air Cleaner. Replaces Lennox models.

Kit includes:

1 – 50A66-843 Ignition Control Board

1 – Wiring harness (9-pin to 12-pin)

1 – Wiring harness (4-pin to 6-pin)

1 – Mounting panel

4 – Stand-off fasteners

1 – Circuit breaker

1 – 4" blue wire

2 – Wiring diagrams

Replace
the Original
with the Original.

21D83M-843 simplifies installation and ensures
peak system performance.

Features:

• Includes diagnostic indicator flash codes

• 3 fan speeds

• Remote flame sense

• Humidifier and electronic air cleaner connections (optional)

Integrated Furnace
Control – 21D83M-843

Single-Stage

OEM
HSI Integrated
Furnace Control Kit

Nitride Ignition Integrated Furnace Control

Controls Gas Valve, Ignitor, Blower, Inducer, Humidifier and Air Cleaner. Replaces Lennox models.

Specifications

Input Voltage: 25 VAC 50 / 60 Hz

Maximum Input Current @ 25 VAC: 0.45 amp

Valve Relay: 1.5 amp @ 25 VAC 50 / 60 Hz 0.6 pf

Ignitor Relay: 2.0 amp @ 120 VAC 50 / 60 Hz (resistive)

Inducer Relay: 2.2 FLA – 3.5 LRA @ 120 VAC

Circulator Relay: 14.5 FLA – 25.0 LRA @ 120 VAC

Operating Temperature Range: -40 to +175°F (-40 to +79°C)

Humidity Range: 5% to 93% relative humidity (non-condensing)

21D83M-843 Cross Reference

21D83M-843 Replaces:

Lennox White-Rodgers

10M9301
12L6901
32M8801
56L8401

24L8501
63K8901
97L4801

100925-01
100925-03
17W9201
23W5101
30W2501
69M0801
69M1501
83M00

50A65-120
50A65-121

50A62-120
50A62-121
50A62-820

21D83M-843
50A66-122
50A66-123

Timing Specifications

(All times are in seconds unless noted otherwise)

21D83M-843

Pre-purge: 15
Heat delay to fan ON 45
Heat delay to fan OFF 60/90/120/180
Cool delay to fan ON 2
Cool delay to fan OFF 2/45
Auto reset 60 minutes

HOT

(LINE)

HUMIDIFIER

ELECTRONIC

AIR CLEANER

FLAME

SENSOR

PROBE

LEGEND

Low Voltage (24 VAC)

Line Voltage (120 VAC)

N. C. = Normally closed switch
N. O. = Normally open switch

Replacement

21D83M-843

TYPICAL SYSTEM WIRING DIAGRAM

120 VAC

24 VAC

TH TR

50A66

FAN
COOL
HEAT
PARK
PARK

LINE

XFMR

EAC
HUM

PARK

IND

IGN
IGN N
IND N

120 VOLT

NEUTRAL

Y

W

G

24 V

HUMIDIFIER

R

C

24 V HUM

FP

PS

HLI

HLO

RO1
GND
RO2

MV
MV
TR
TH

(E2)

(E33)

24 VAC CLASS II
TRANSFORMER

INDUCER

IGNITOR

Y

W

G

R

THERMOSTAT

PRESSURE SWITCH (N. O.)

HIGH LIMIT

(N. C.)

ROLLOUT

(N. C.)

CIRCULATOR

BLOWER

COMPRESSOR

CONTACTOR

AUX. HIGH

LIMIT (N. C.)

GAS

VALVE

NEUTRAL

(LINE)

Saint Louis, Missouri Markham, Ontario

314-553-3600 905-948-3411

www.white-rodgers.com

www.emersonclimate.com

The Emerson logo is a trademark and
a service mark of Emerson Electric Co.

WR-8273