Goodman ComfortNet Service manual

Service Instructions

ComfortNet™

ASXC, DSXC, and GSXC Condensing Units,

ASZC & DSZC Split System Heat Pumps

with R-410A Refrigerant

Blowers, Coils, & Accessories

This manual is to be used by qualified, professionally trained HVAC technicians only. Goodman
does not assume any responsibility for property damage or personal injury due to improper
service procedures or services performed by an unqualified person.

Copyright © 2015-2017 Goodman Manufacturing Company, L.P.

is a registered trademark of Maytag Corporation or its related companies and is used under license to Goodman Company, L.P., Houston, TX. All rights reserved.

RS6200007r12

September 2017

IMPORTANT INFORMATION

Pride and workmanship go into every product to provide our customers with quality products. It is possible, however, that
during its lifetime a product may require service. Products should be serviced only by a qualified service technician who is
familiar with the safety procedures required in the repair and who is equipped with the proper tools, parts, testing instruments
and the appropriate service manual. REVIEW ALL SERVICE INFORMATION IN THE APPROPRIATE SERVICE MANUAL BEFORE

BEGINNING REPAIRS.

IMPORTANT NOTICES FOR CONSUMERS AND SERVICERS

RECOGNIZE SAFETY SYMBOLS, WORDS AND LABELS

WARNING

O

NLY PERSONNEL THAT HAVE BEEN TRAINED TO INSTALL, ADJUST, SERVICE OR

REPAIR (HEREINAFTER

MANUAL SHOULD SERVICE THE EQUIPMENT

BE RESPONSIBLE FOR ANY INJURY OR PROPERTY DAMAGE ARISING FROM

IMPROPER SERVICE OR SERVICE PROCEDURES

ASSUME RESPONSIBILITY FOR ANY INJURY OR PROPERTY DAMAGE WHICH MAY

RESULT

. IN

LICENSES TO SERVICE THE EQUIPMENT SPECIFIED IN THIS MANUAL, ONLY

LICENSED PERSONNEL SHOULD SERVICE THE EQUIPMENT

INSTALLATION, ADJUSTMENT, SERVICING OR REPAIR OF THE EQUIPMENT

SPECIFIED IN THIS MANUAL, OR ATTEMPTING TO INSTALL, ADJUST, SERVICE OR

REPAIR THE EQUIPMENT SPECIFIED IN THIS MANUAL WITHOUT PROPER

TRAINING MAY RESULT IN PRODUCT DAMAGE, PROPERTY DAMAGE, PERSONAL

INJURY OR DEATH

, “

SERVICE

”)

THE EQUIPMENT SPECIFIED IN THIS

. THE

MANUFACTURER WILL NOT

. IF

YOU SERVICE THIS UNIT, YOU

ADDITION, IN JURISDICTIONS THAT REQUIRE ONE OR MORE

. I

MPROPER

.

T

O PREVENT THE RISK OF PROPERTY DAMAGE, PERSONAL INJURY, OR DEATH,

DO NOT STORE COMBUSTIBLE MATER IALS OR USE GASO LINE OR OTHER

FLAMMABLE LIQUIDS OR VAPORS IN THE VI CINITY OF T HIS APPLIANCE.

To locate an authorized servicer, please consult your telephone book or the dealer from whom you purchased this product.
For further assistance, please contact:

CONSUMER INFORMATION LINE

GOODMAN® BRAND PRODUCTS

TOLL FREE

1-877-254-4729 (U.S. only)

email us at: [e-mail]

fax us at: [phone]

(Not a technical assistance line for dealers.)

Outside the U.S., call 1-713-861-2500.

(Not a technical assistance line for dealers.) Your telephone company will bill you for the call.

is a registered trademark of Maytag Corporation or its related companies and is used under license to Goodman Company, L.P., Houston, TX. All rights reserved.

email us at: [e-mail]

AMANA® BRAND PRODUCTS

TOLL FREE

1-877-254-4729 (U.S. only)

fax us at: [phone]

(Not a technical assistance line for dealers.)

2

IMPORTANT INFORMATION

SAFE REFRIGERANT HANDLING

While these items will not cover every conceivable situation, they should serve as a useful guide.

WARNING

REFRIGERANTS ARE H EAVIER THAN AIR. THEY CAN "PUSH OUT" THE

OXYGEN IN YOUR LUNGS OR IN ANY ENCLOSED SPACE.

POSSIBLE DIFFICULTY IN BREATHIN G OR D EATH:

EVER PURGE REFRIGERANT INTO AN ENCLOSED ROOM OR SPACE. BY

•

N

LAW, ALL REFRIGERANTS MUST BE RECLAIMED.

IF AN INDOOR LEAK IS SUSPECTED, THOROUGHLY VENTIL ATE THE AREA

•

BEFORE BEGINNING WORK.

IQUID REFRIGERANT CAN BE VERY COLD. TO AVOID POSSIBLE FROST-

•

L

BITE OR BL INDNESS, AVOID CONTACT WITH REFRIGERANT AND WEAR

I

GLOVES AND GOGGLES.

SKIN OR EYES, SEEK MEDICAL HELP IMMEDIATELY.

A

LWAYS FOLLOW

•

AS POIS ONOUS GAS WI LL BE PRODUCED .

F LIQUID REFRIGERANT DOES CONTACT YOUR

EPA

REGULATIONS. NEVER BURN REFRIGERANT,

O AVO ID

T

WARNING

HE UNITED STATES ENVIRONMENTAL PROTECTION AGENCY ( "

T

HAS ISSUED VARIOUS REGULATIONS REGARDING THE INTRODUCTION AND

DISPOSA L OF REFRIGERANTS INTRODUCED INTO THIS UNIT.

FOLLOW THESE REGULATIONS MAY HARM THE ENVI RONMENT AND CAN

LEAD TO THE H IMPOSITION OF SUBSTANTIAL FINES.

MAY VARY BY JURISDICTION.

EPA OFFICE.

LOCAL

SHOULD QUEST IONS ARISE, CO NTACT YOUR

THESE REGULATIONS

EPA

AILURE TO

F

WARNING

TO AVOID POSSIBLE EXPLOSION:

EVER APPL Y FLAME OR STEA M TO A REFRIGERAN T CYLINDER. IF YOU

•

N

MUST HEA T A CYLINDER FOR FASTER CHARGING, PARTIALLY IMMERSE

IT IN WARM WATER.

NEVER FILL A CYLIN DER MORE THAN 80% FU LL OF LIQUID REFRIGER ANT.

•

NEVER ADD ANYTHING OTHER THAN R-22 TO AN R-22 CYLINDER OR

•

R-410 A TO AN R-410A CYLINDER. THE SERVICE EQUIPMENT USED MUST

BE LISTED OR CERTIFIED FOR THE TYPE OF REFRIGERANT USED.

TORE CYLINDERS IN A COOL, DRY PLACE. NEVER US E A CYLINDER

•

S

AS A PLATFORM OR A ROLLER.

WARNING

TO AVOID POSSIBLE EXPLOSION, USE ONLY RETURNABLE (NOT DISPOSABLE)

SERVICE CYLINDERS WHEN REMOVING REFRIGERANT FROM A SYSTEM.

•

ENSURE THE CYLINDER IS FREE OF DAMAGE WHICH COULD LEAD TO A

LEAK OR EXPLOS ION.

•

")

ENSURE THE HYDROSTATIC T EST DATE DOES NOT EXCEED 5 YEARS.

•

ENSURE THE PRESSURE RATING MEETS OR EXCEEDS 400 LBS.

WHEN IN DOUBT, DO NOT USE CYLINDER.

WARNING

WARNING

SYSTEM CONTAMINANTS, IMPROPER SERVICE PROCEDURE AND/OR PHYSICAL

ABUSE AFFECTING HERMETIC COMPRESSOR ELECTRI CAL TERMINALS MAY

CAUSE DANGEROUS SYSTEM VENTING.

The successful development of hermetically sealed refrigera­tion compressors has completely sealed the compressor's
moving parts and electric motor inside a common housing,
minimizing refrigerant leaks and the hazards sometimes
associated with moving belts, pulleys or couplings.

Fundamental to the design of hermetic compressors is a
method whereby electrical current is transmitted to the
compressor motor through terminal conductors which pass
through the compressor housing wall. These terminals are
sealed in a dielectric material which insulates them from the
housing and maintains the pressure tight integrity of the
hermetic compressor. The terminals and their dielectric
embedment are strongly constructed, but are vulnerable to
careless compressor installation or maintenance proce­dures and equally vulnerable to internal electrical short
circuits caused by excessive system contaminants.

T

O AVOID POSSIBLE INJURY, EX PLOSI ON OR DEATH, PRACTICE SAFE

HANDLING OF RE FRIGERA NTS.

In either of these instances, an electrical short between the
terminal and the compressor housing may result in the loss
of integrity between the terminal and its dielectric embed­ment. This loss may cause the terminals to be expelled,
thereby venting the vaporous and liquid contents of the
compressor housing and system.

A venting compressor terminal normally presents no danger
to anyone, providing the terminal protective cover is properly
in place.

If, however, the terminal protective cover is not properly in
place, a venting terminal may discharge a combination of

(a) hot lubricating oil and refrigerant

(b) flammable mixture (if system is contaminated

with air)

in a stream of spray which may be dangerous to anyone in the
vicinity. Death or serious bodily injury could occur.

Under no circumstances is a hermetic compressor to be
electrically energized and/or operated without having the
terminal protective cover properly in place.

See Service Section S-17 for proper servicing.

3

PRODUCT IDENTIFICATION

s

AS X C 16 024 1 AA

1 2 3 4,5 6 6 7 8,9

ComfortNet™

Brand

A - Amana ® bran d Maj or/Mi nor Revi si on

D - Deluxe Goodman® brand

G - Goodman® brand

Type 1 - 208/230V Single-Phase 60 Hz

S 3 - 208/230V Three-Phase 60 Hz

Split Sys tem

4 - 460V Three-Phase 60 Hz

Type

C: Condenser R-22

H: Heat Pump R-22 024 - 2 Tons

X: Condenser R-410A 036 - 3 Tons

Z: Heat Pump R-410A 048 - 4 Tons

060 - 5 Tons

Communication Feature

C: 4-Wi re Communicati on Ready

SEER

16 - 16 SEER

18 - 18 SEER

Engineering

Voltage

Nominal Capacity

4

PRODUCT IDENTIFICATION

A

=

ComfortNet™

CAP F 1824 A 6 A

1 2 3 4 5,6,7,8 9 10 11,12

Brand Engineering*

C Indoor Coi l

Unit Application 2 = R-22

A Upflow/Downflow Coi l

H Horizontal A-Coil

Horizontal Slab Coil

S

Coated Coils

T

Nominal Width for Gas Furnace

A = Fits 14" Furna ce Cabinet

B = Fits 17-1/2" Furnace Cabi net

C =

Fits 21" Furnace Cabinet

D = Fits 24-1/2" Furnace Cabinet
N

Does Not Apply (Horizontal Slab Coils

Major/Minor Revisions

Refrigerant Charge

4 = R-410A

6 = R-410A or R-22

Cabinet Finish

U Unpainted

PPainted

N Unpai nted Case

Expansion Device

FFlowrator
T 4 - 5 Tons

Expansi on Valve 4 - 5 Tons

1824 =

3030 =

3131 =

3636 =

3642 =

3743 =

4860 = Factory-Installed Non-Adjustable

4961 =

Nominal Capacity @ 13 SEER

1-1/2 - 2 Tons

2-1/2 Tons

2-1/2 Tons

3 Tons

3 - 3-1/2 Tons

3 - 3-1/2 Tons

5

PRODUCT IDENTIFICATION

H

MB V C 12 00 A A 1

1,2 3 4 4 5,6 7 8 9

ComfortNet™

Brand

MB - Modular Blower 1: 208-230V/60Hz/1 P

Type A: First Seri es

Speed

V:

Communication Feature A: No Circui t Br eaker

C: 4-Wire Communication Ready

Airflow

12:

1200 CFM

16:

1600 CFM

20:

2000 CFM

B: Ci rcuit Breaker

Elect rical

Design Se ries

Circuit Breaker

Factory Heat

00 No Heat

6

PRODUCT IDENTIFICATION

A V P T C 1830 1 6 AA

1 2 3 4 5 6,7,8,9 11 12 13,14

ComfortNet™

Brand

A Airhandler

Unit Application

Vari a bl e Sp eed Motor

V

Cabinet Finish

U: Unpa inted

P: Painted 1 208/240V, 1 Phase, 60 Hz

N: Uncas ed

Expansion Device

F: Flowrator

T: Expans ion Valve

Communications

C: 4-Wire Communi cati on Ready

Multi-Position & Downflow Applications

Ceiling Mount & Wall Mount Applications

Maj or/Mi nor Revi si ons

1830 = 1-1/2 to 2-1/2 Tons

3137 = 3 Tons

4260 = 3-1/2 to 5 Tons

Engineering*

Refrigerant Charge

No Di git = R-22 Onl y

6 = R-410A or R-22

Electrical

Nominal Capacity

7

PRODUCT IDENTIFICATION

A

V

PTC 18 B 1 4 AA

1 2 3 4 5 6,7 8 9 10 11,12

ComfortNet™

Brand

A Si ngl e Piec e

Ai rhandl er

Unit Application

C Ceiling Mount PSC Motor 4 = R-410a

R Multi Position PSC Motor

S Multi Posi tion EEM Motor

W Wall Mount PSC/EEM Motor 1 208/240V, 1 Phase, 60 Hz

VMulti Position

Variable Speed Motor -

Communi cating

Cabinet Finish

U Unpainted

PPainted

NUncased

Expansion Device

FFlowrator 31 = 2 Tons

TExpansion Valve 33 = 1 1/2 - 2 Tons

Communications

ComfortNet

C

TM

Compatible

*Not used for inventory management

Nominal Capacity

Major/Minor Revisions

18 = 1-1/2 Tons

24 = 2 Tons

25 = 2 Tons

29 = 2 Tons

30 = 2-1/2 Tons

36 = 3 Tons

37 = 2 1/2 - 3 1/2 Tons

39 = 2 1/2 - 3 Tons

42 = 3-1/2 Tons

48 = 4 Tons

49 = 3 - 3 1/2 Tons

59 = 4 - 5 Tons

60 = 5 Tons

61 = 4 - 5 Tons

Engineering*

Refrige rant Charge

Electrical

Cabinet Width

B = 17-1/2"

C = 21"

D = 24-1/2"

All Airhandlers use DIRECT DRIVE MOTORS. Power supply is AC 208-230v, 60 hz, 1 phase.

8

PRODUCT IDENTIFICATION

ASXC1 6

MANA® BRAND SPLIT

A

Model/Rev Description

ASXC160**1AA

ASXC160601BA Use ZPS49 compressor.

ASXC160481BA SmartCoil® coils

ASXC160(24/36)1BB Wiring diagram updated with notes.

ASXC160(48-60)1BB Motor changed to Nidec.

Introduces Amana® brand 2-stage 16 SEER condensing units with R-410A,
communic ating models.

OMMUNICATING CONDENSERS R-410A 16 SEER

X-C

ASXC160(24/36)1BC
ASXC160(48-60)1BC

ASXC160(24/36)1BD
ASXC160(48-60)1BD

ASXC160(241, 481)BE Refrigerant charge reduction

ASXC160(24,36,48,60)1CA 16 SEER 2-Stage AC Development with improved performance.

Ultratech® 2.0 compressor change.

Replaced PCBHR103 Communicating Heat Pump Control Board with PCBHR104
Communicating Heat Pump Control Board.

ASXC18

MANA® BRAND SPLIT

A

Model/Rev Description

ASXC18**1AA

ASXC180(36/48/60)1AB Wiring diagram updated with notes.

ASXC180(36/48-60)1AC Replaced compressors ZPS20K4EPFV230 with ZPS20K5EPFV130 and compressor

Initial release of Amana® brand 2-stage 16 SEER condensing units with R-410A,
communicating models.

ZPS30K4EPFV230 with ZPS30K5EPFV130.

OMMUNICATING CONDENSERS R-410A 18 SEER

X-C

ASXC180(24/36/48/60)1BA 18 SEER 2-Stage AC Development with improved performance.

9

PRODUCT IDENTIFICATION

GSXC1 6

OODMAN® BRAND SPLIT

G

Model/Rev Description

GSXC160( 24/36/48/60)1CA

OODMAN® BRAND SPLIT

G

Model/Rev Description

GSXC180( 24/36/48/60)1BA

OMMUNICATING CONDENSERS R-410A 16 SEER

X-C

16 SEER 2-Stage AC Development with improved performance.

GSXC1 8

OMMUNICATING CONDENSERS R-410A 18 SEER

X-C

18 SEER 2-Stage AC Development with improved performance.

10

PRODUCT IDENTIFICATION

DSXC1 6

ELUXE SPLIT

D

Model/Rev Description

DSXC160**1AA

DSXC160(24/36)1AB Wiring diagram updated with notes.

DSXC160(24/36)1AC
DSXC160(48-60)1BC

DSXC160481BA SmartCoil® coils.

DSXC160601BA ZPS49K compressor.

DSXC160(48-60)1BB Motor changed to Nidec.

DSXC160241AF
DSXC160481BE

Initial releas e of Goodman® Deluxe brand 2-stage 16 SEER condensing units with R­410A, communicating models.

Ultratech® 2.0 compressor.

Refrigerant charge reduction

OMMUNICATING CONDENSERS R-410A 16 SEER

X-C

DSXC1 8

DELUXE SPLIT X-C

Model/Rev Description

DSXC18**1AA

DSXC180(36/48/60]1AB W iring diagram updated with notes.

DSXC18036AC

DSXC180(48-60)1AC Ultratech® 2.0 compressor change.

Initial releas e of Goodman® Deluxe brand 2-stage 18 SEER condensing units with R­410A, c ommunicating models.

Replaced compressors ZPS20K4EPFV230 with ZPS20K5EPFV130 and compressor
ZPS30K4EPFV230 with ZPS30K5EPFV130.

OMMUNICATING CONDENSERS R-410A 18 SEER

11

PRODUCT IDENTIFICATION

ASZC16

MANA® BRAND SPLIT

A

Model/Rev Description

ASZC160**1AA

ASZC160(24/36)1AB
ASZC160(48/60)1AB

ASZC160(24-48)1AC
ASZC160601BA

ASZC160(24-36])1AD
ASZC160601BB

ASZC160(24-36)1AE

ASZC160481AE Ultratech® 2.0 compressor change.

Introduces Amana® brand 2-stage 16 SEER heat pump units with R-410A,
communicating models.

Sanhua (RANCO) revers ing valves

Release of models with accumulators and crankcase heaters.

Motor changed to Nidec.

Replaced compressors ZPS20K4EPFV230 with ZPS20K5EPFV130 and compressor
ZPS30K4EPFV230 with ZPS30K5EPFV130.

OMMUNICATING HEAT PUMP R-410A 16 SEER

Z-C

ASZC18

MANA® BRAND SPLIT

A

Model/Rev Description

OMMUNICATING HEAT PUMPS R-410A 18 SEER

Z-C

ASZC180**1AA

ASZC180601BC
ASZC180601BB

ASZC180(36/48/60)1AB Release of models with accumulators and crankcase heaters.

ASZC180(36-4)]1AC
ASZC180601BA
ASZC180361AD

Introduces Amana® brand 2-stage 18 SEER heat pump units with R-410A,
communicating models.

Ultratech® 2.0 c ompressor change.

Sanhua (RANCO) revers ing valves

12

PRODUCT IDENTIFICATION

DSZC16

ELUXE SPLIT

D

Model/Rev Description

DSZC16**1AA

DSZC160(24/36)1AB
DSZC160(48/60)1AB

DSZC160(24-48)1AC
DSZC160601BA

DSZC160(24-48)]1AD
DSZC160601BB
DSZC160481AE
DSZC160601BC

DSZC160(24-36)1AE

Initial releas e of Goodman® brand Deluxe 2-stage 16 SEER heat pump units with R­410A, communicating models.

Sanhua (RANCO) revers ing valves.

Release of models with accumulators and crankcase heaters.

Ultratech® 2.0 c ompressor change.

Replaced compressors ZPS20K4EPFV230 with ZPS20K5EPFV130 and compressor
ZPS30K4EPFV230 with ZPS30K5EPFV130.

OMMUNICATING HEAT PUMP R-410A 16 SEER

Z-C

DSZC18

DELUXE SPLIT Z-C

Model/Rev Description

DSZC18**1AA

Initial releas e of Goodman® brand Deluxe 2-stage 18 SEER heat pump units with R­410A, c ommunicating models.

OMMUNICATING HEAT PUMP R-410A 18 SEER

DSZC180(36/48/60)1AB Sanhua (RANCO) reversing valves.

DSZC180361AD

DSZC180(36-48)1AC
DSZC180601BA

DSZC160(24-48)1AD
DSZC160601BB

Replaced compressors ZPS20K4EPFV230 with ZPS20K5EPFV130 and compressor
ZPS30K4EPFV230 with ZPS30K5EPFV130.

Release of models with accumulators and crankcase heaters.

Ultratech® 2.0 c ompressor change.

AVPTC****14

SINGLE PIECE AIR HANDLER MULTIPLE-POSITION VARIABLE SPEED

AINTE D TXV WITH 4-WIRE COMMUNICATING CONTROL

P

Model/Rev Description

AVPTC183014AA
AVPTC313714AA
AVPTC426014AA

AVPTC183014AB
AVPTC313714AB
AVPTC426014AB

Initial release of 13 SEER air handler with communicating control and serial
communicating indoor blower motor.

Replaced PCBJA10 communic ating air handler control board with PCBJA103.

13

PRODUCT IDENTIFICATION

AVPTC**14

SINGLE PIECE AIR HANDLER MULTIPLE-POSITION VARIABLE SPEED

AINTED TXV W ITH 4-W IR E COMMUNICATING CONTROL

P

Model/Rev Description

AVPTC24B14AA
AVPTC(30/36)C14AA
AVPTC(42/48/60)D14AA

AVPTC48C14AA Updated S&R and travel labels.

Initial release of 13 SEER air handler with communicating control and serial
communicating indoor blower motor. Redesign of AVPTC models to new air handler
cabinetry. Incorporated 4-way, mult-position body utilized on ARTP/ASPt mdoels.

AVPTC(42/48/60)14AB

AVPTC60D14AC Serial plate update

AVPTC24B14AC
AVPTC30C14AB

AVPTC25B14AA
AVPTC29B14AA
AVPTC31C14AA
AVPTC37B14AA
AVPTC37C14AA
AVPTC37D14AA
AVPTC49D14AA
AVPTC59C14AA
AVPTC59D14AA
AVPTC61D14AA

AVPTC33C14AA
AVPTC39C14AA
AVPTC49C14AA

AVPTC35B14AA Introducing 2.5 and 3 Ton Air Handler product lines.

Redesign of AVPTC models to new air handler cabinetry. Incorporated 4-way, mult­position body utilized on ARTP/ASPt mdoels.

Heater Kit airflow update.

AVPTC Efficiency Upgrades
The new AVPTC redesign will incorporate the upgrade blower, coil pan and coil design
intended to increase efficienc y and standardize production.

Upgrade the current AVPTC C-49 cabinets to include 1. quality improvements captured in
Ready15 design. 2.include redesigned drain pan, Morris on blower housing and Emerson
NXT Booster Charge Adjustable TXV.

AVPTC[31,37,39,49,59]C14AB
AVPTC[37,59,61]D14AB

AVPTC[25,29, 37]B14AB
AVPTC33C14AB
AVPTC[31, 37,39,49,59]C14AC
AVPTC49D14AB
AVPTC[37,59,61]D14AB

14

Revisions because of New Heater kits released

Air handler revisions due to using an upgraded (thicker with higher R value)
Quietflex wrapper insulation.

PRODUCT IDENTIFICATION

MBVC

ODULAR BLOWER AIR HANDLER V-MULTI-POSITION VARIABLE-SPEED

M

OMMUNICATING READY W/4-WIRES

C

Model/Rev Description

MBVC1200AA1-AA
MBVC1600AA1-AA
MBVC2000AA1-AA

MBVC1200AA1-AB
MBVC1600AA1-AB
MBVC2000AA1-AB

MBVC1200AA1-AC
MBVC1600AA1-AC
MBVC2000AA1-AC

MBVC1200AA1-AD
MBVC1600AA1-AD
MBVC2000AA1-AD

MBVC[1200,1600,2000]AA1-AE Release of MBR/MBVC Models(Minor Revisions) for 11th St Plant. - Dayton to Houston

Introduction of module blower with variable speed blower motor with the new
communicating control & serial communicating indoor blower motor.

Introduction of a module blower with variable speed blower motor with communicating
control & serial communicating indoor blower motor. Replaces exis ting Emerson motors
(013M00111 & 013M00112).

Introduction of a module blower with variable speed blower motor with communicating
control & serial communicating indoor blower motor. Quality improvement to use 0.75"
Quiet Flex Insulation.

Introduction of a module blower with variable speed blower motor with communicating
control & serial communicating indoor blower motor. Introduces a new Communicating Air
Handler Control Board (PC).

MBVC[1200,1600,2000]AA1-AF

Add permanent sealing/condensation-control upgrades to all MB units and remove high­voltage knockouts

CAUF

INDOOR COIL A-UPFLOW/DOWNFLOW UNCASED FLOW RATOR

C-

Model/Rev Description

CAUF*****6AA Initial release of CAUF Dayton Upflow/Downflow coils.

CAUF*****6BA Burr Oak Louvered Fin released in place of the Wavy Fin.

CAUF****6*DA Replaced

CAUF*****6DB Drain pan material changed.

CAUF1824A6RDB
CAUF1824B6RDB

CAUF36***CA Redesign from 2 row to 3 row for performance improvement .

CAUF3030(A/B)6RDB
CAUF3030(C/D)6RDB
CAUF3131(B/C)6RDB

Manufacturing Location Change from Dayton to Houston. Designated by "R".

Manufacturing Location Change from Dayton to Houston. Designated by "R".

existing copper coils and other associated parts with aluminum components.

15

PRODUCT IDENTIFICATION

CHPF

-INDOOR COIL HORIZONT AL A-COIL PAINTED FLOWRATOR

C

Model/Rev Description

CHPF*****6AA Intial release of 13 SEER CHPF horizontal A coil.

CHPF*****6BA

CHPF1824A6CA
CHPF2430B6CA
CHPF3636B6CA
CHPF3642C6CA
CHPF3642D6CA
CHPF3743C6BA
CHPF3743D6BA
CHPF4860D6DA

CHPF1824A6CB
CHPF2430B6CB
CHPF3636B6CB
CHPF3642C6CB
CHPF3642D6CB
CHPF3743C6BB
CHPF3743D6BB
CHPF4860D6DB

CHPF1824A6CC
CHPF2430B6CC
CHPF3636B6CC
CHPF3642C6CC
CHPF3642D6CC
CHPF3743C6BC
CHPF3743D6BC
CHPF4860D6DC

Released Burr Oak Louvered Fin in place of the Wavy Fin. The rows changed by one, (i.e.
4 row to 3 row; 3 row to 2 row) where applicable.

Louvered fins. Replac ed copper tube hairpins with aluminum hairpins.

Drain pan material c hange to a Decabromodiphenyl Ether free resin.

Change to prepainted wrappers

16

PRODUCT IDENTIFICATION

CAPF

INDOOR C OIL A-UPFLOW/DOWNFLOW PAINTE D FLOW RATOR

C-

Model/Rev Description

CAPF*****6AA Initial release of CAPF Dayton Upflow/Downflow coils.

CAPF*****6BA Burr Oak Louvered Fin released in place of the Wavy Fin.

CAPF36***CA Redesigned for performance improvement from 2 row to 3 row.

CAPF*****6DA Replaced existing copper coils and other associated parts with aluminum components.

CAPF*****6DB Drain pan material changed.

CAPF1824A6DC
CAPF1824B6DC
CAPF1824C6DC
CAPF3030A6DC
CAPF3030B6DC
CAPF3030C6DC
CAPF3030D6DC
CAPF3131B6DC
CAPF3131C6DC
CAPF3137B6AB
CAPF3636A6DC
CAPF3636B6DC
CAPF3636C6DC
CAPF3636D6DC
CAPF3642C6DC
CAPF3642D6DC
CAPF3743C6DC
CAPF3743D6DC
CAPF4860C6DC
CAPF4860D6DC
CAPF4961C6DC
CAPF4961D6DC

Redesign the wrapper for the CAPF to provide increased ease of installation.

CAPT

INDOOR

C-

Model/Rev Description

CAPT3131B4BA
CAPT3131C4BA

CAPT3743C4AA
CAPT3743D4AA

CAPT4961C4AA
CAPT4961D4AA

CAPT3131B4AB
CAPT3131C4AB
CAPT3743C4AB
CAPT3743D4AB
CAPT4961C4AB
CAPT4961D4AB

COIL

UPFLOW/DOWNFLOW PAINTED CAS ED FLOWRATOR W/TXV

A-

Initial releas e of coils with factory-installed, non-adjus table TXV. Single stage AHRI ratings
for CAPT3131 NTC combinations.

Initial releas e of single stage AHRI ratings for CAPT3743 NTC combinations.

Initial releas e of single stage AHRI ratings for CAPT4961C4 NTC combinations.

Redesign the wrapper for the CAPT to provide increased ease of installation.

17

PRODUCT IDENTIFICATION

CSCF

INDOOR C OIL S-HORIZONTAL SLAB COIL C-UNPAINTED FLOW RATOR

C-

Model/Rev Description

CSCF*****6AA Initial release of 13 SEER CSCF horizontal slab coils.

CSCF*****6BA

CSCF1824N6BB
CSCF3036N6BB
CSCF3642N6CB
CSCF4860N6CB

CSCF1824N6CA
CSCF3036N6CA
CSCF3642N6CA
CSCF4860N6CA

Burr Oak Louvered Fin released in place of the W avy Fin. Rows reduced by one where
applicable.

Drain pan material changed.

Replaced copper coils and other associated parts with aluminum components.

18

ACCESSORIES

ComfortNet™

ASXC/DSXC 16
ASXC/DSXC/GSXC 18

Model Description

ABK-20 Anc hor Bracket Kit X X X X X X X X

ASXC16024

DSXC16024

ASXC16036

DSXC16036

ASXC16048

DSXC16048

ASXC16060

DSXC16060

ASXC18024

DSXC18024

GSXC18024

ASXC18036

DSXC18036

GSXC18036

ASXC18048

DSXC18048

GSXC18048

ASXC18060

DSXC18060

GSXC18060

TX2N4A TXV Kit

TX3N4 TXV Kit

TX5N4 TXV Kit

CSR-U-1 Hard-start Kit

CSR-U-2 Hard-start Kit

CSR-U-3 Hard-start Kit

1

FSK01A

LSK02*

B1141643

* Contains 20 brackets; four brackets needed to anchor unit to pad.

Installed on the indoor coil.

Available in 24V legacy mode only. This feature is integrated in the communicating mode.

This component is included in the CTK0*** communicating thermostat kit.

Freeze Protecti on Kit

Liqui d Line S olenoid

Valv e

3

24V Transformer

XX

XX

XX X X

XX

XX

XX X X

XXXXX X X X

XXXXX X X X

XXXXX X X X

ASZC/DSZC 16
ASZC/DSZC 18

Model Description

ASZC16024
DSZC16024

ABK-20Anchor Bracket KitXXXXXXX

1

TX2N4

TX3N4

TX5N4

TXV Kit X

1

TXV Kit X X

1

TXV Kit X X X X

CSR-U-1 Hard-start Kit X X X

CSR-U-2 Hard-start Kit X X X X X X

CSR-U-3 Hard-start Kit X X X X

2

FSK01A

LSK02*

OT18-60A

B1141643

Freeze Protection KitXXXXXXX

Liquid Line Solenoid

Valv e

Outdoor Thermos tat/

3

Lock out Thermostat

4

24V TransformerXXXXXXX

XXXXXXX

XXXXXXX

ASZC16036
DSZC16036

ASZC16048
DSZC16048

ASZC1 606 0
DSZC1 606 0

ASZC18036
DSZC18036

ASZC18048
DSZC18048

ASZC18060
DSZC18060

* Contains 20 brackets; four brackets needed to anchor unit to pad

1

Field-installed, non-bleed, ex pansion valve kit - Condensing units and heap pumps with reciprocating compressors require the
use of start-ass ist components when used in c onjunction with an indoor coil using a non-bleed thermal ex pansion valve
refrigerant

2

Installed on the indoor coil

3

Available in 24V legacy mode only. This feature is integrated in the communicating mode. Required for heat pump applications
where ambient temperature fall below 0 °F with 50% or higher relative humidity.

4

This component is included in the CTK0*** communicating thermostat kit.

19

ACCESSORIES

EXPANSION VALVE KITS

1/4 FLARE CONNECTION

BULB TO BE LOCATED
AT 10 OR 2 O'CLOCK

For Applications requiring

a field installed access fitting

EVAPORATOR COIL

EVAPORATOR COIL

1/4' FLARE
CONNECTION

SEAL SUPPLIED W/ KIT

REMOVE BEFORE INSTALLING EXPANSION VALVE

SUCTION LINE

BULB

EXPANSION VALVE

SUCTION LI NE

EXPAN SION VALV E

BULB

SEAL SUPPLIED W/ KIT

BULB TO BE LOCATED
AT 10 OR 2 O'CLOCK

DISTRIBUTOR
BODY

For Applications not requiring

a field installed access fitting

DISTRIBUTOR
BODY

7/8" NUT

PISTON

SEAL

PISTON

SEAL

TAILPIECE

3/8"­SWEAT

TAILPIECE

3/8"­SWEAT

SEAL SUPPLIED W/ KIT

20

REMOVE BEFORE
INSTALLING
EXPANSION VALVE

SEAL SUPPLIED W/ KIT

7/8" NUT

ACCESSORIES

Wire Nut

FSK01A

FREEZE THERMOSTAT

KIT

Y

k

c

a

l

B

k

c

a

l

B

Wire Nut

Y

Install Line

Thermostat

Here

Install Line

Thermostat

Here

B

l

a

c

B

l

Wire Nut

Wire Nut

Y

k

a

c

k

Y

21

ACCESSORIES

BLOW ER

ELECTRI C HEAT KIT

NO HEAT

MBVC1200AA-1**

MBVC1600AA-1**

MBVC2000AA-1**

X = Allowable combinations

- = Restricted combinations

- XXXXXX - - -

- XXXXXX - - -

- XXXXX - X - -

ELECTRIC HEAT KIT APPLICATIONS - MBVC

HKR-03*

^ = Circuit 1: Single Phase for Air Handler Motor
Circuit 2: 3-Phase for HKR3 Heater Kits

HKR05-(C)'

HKR-06*

HKR-08(C)*

HKR-10(C)*

HKA-15C*

HK* SERIES ELETRIC HEAT KITS -

HKA-20C*

^HKR3-15*

^HKR3-20A

22

ACCESSORIES

ELECTRIC HEAT KIT APPLICATIONS - AVPTC

MODE LS HKR-03* H KR-05*/ -05C* HKR-06 * HKR-08*/-08C* HKR-10*/ -10C* H KR-15C* HKR-20C* HKR-21 C* HK A-15C* HKA-20C*

AVPTC183014A* X X X

AVPTC313714A* X X X

AVPTC426014A* X X X X X X X3 X3 X

* Revision level that may or may not be designated.

C Circuit breaker option.

NOTE:

When 8kW and 10kW heat kits are used with an AVPTC1830 and AVPTC3137, matched with 2- ton outdoor unit, see Note 1 below.

1

Set Heater Kit dip switches 9, 10 and 11 to 6kW setting (9-ON, 10-OFF,11-ON) to obtain 840 CFM.

2

This heater kit can only be used for ‘1000 CFM or higher’ applications.

3

This heater kit can only be used for ‘1200 CFM or higher’ applications.

1

X

1

X

1

X

1

X

--- --- --- --- ---

X2 --- ---

2

X

X

3

X

23

ACCESSORIES

p

p

p

p

p

AVPTC**14**

Heat Kit A pplications

Type / M odel 24B14-A* 30C14-A* 36C14-A* 48C14-A* 42D14-A*

HKSX03XC X X X

HKSX05XC XXXXXXX

HKSX06XC XXXXXXX

HKSX08XC XXXXXXX

HKSX10XC XXXXXXX

HKSX15XF* XXXXX

HKSX20XF* XXXXX

HKSC05XC XXXXXXX

HKSC08XC XXXXXXX

HKSC10XC XXXXXXX

HKSC15XA XXXXX

HKSC15XB XXXXX

HKSC15XF* XXXXX

HKSC19CA* X X

HKSC19CB* X X

HKSC20DA XXX

HKSC20DB XXX

HKSCX20XF* XXXXX

HKSC25DC* XX

* Revis io n level that may or m ay no t be designat ed.

Refer to t he minimum airflow requireme nts fo r each o f the heat k its.

AVPTC

†

48D14-A*

††

60D14-A*

†††

†For match u p wi th a 2 ton outdoo r uni t: Hea ter ki t ap plica Ɵon shall not exceed 10 kW.

Ai rflow fo r 5 kW u

††For ma tch u

Airflo w for 5 kW u

†††For ma tch u

Airflow for 5 kW u

** 3 kW heater kit is not applicable for this indoor application.

to 10 kW hea ter kits s hall be s et to 850 cfm speed tap of ON-ON-ON.

wi th a 3 to n ou tdoor uni t: Hea ter ki t applicaƟon shall not exceed 15 kW.

to 15 kW hea ter ki ts s hal l b e s et to 1400 cfm speed tap of ON-ON-OF F.

wi th a 3.5 ton ou tdoo r uni t: Hea ter ki t applicaƟon shall not exceed 20 kW.

to 20 kW hea ter ki ts s hal l be se t to 1620 cfm speed tap of ON-ON-OFF

24

ACCESSORIES

READY 15 AVPTC

Model AVPTC25B14 AVPTC29B14 AVPTC31C14 AVPTC33C14 AVPTC35B14 AVPTC39C14 AVPTC37B14 AVPTC37C14 AVPTC37D14 AVPTC49C14 AVPTC49D14 AVPTC59C14 AVPTC59D14 AVPTC61D14

HKSX03XC XX XX X

HKSX05XC XXXXXXXXXXXXXX

HKSX06XC XXXXXXXXXXXXXX

HKSX08XC XXXXXXXXXXXXXX

HKSX10XC XXXXXXXXXXXXXX

HKSC05XC XXXXXXXXXXXXXX

HKSC08XC XXXXXXXXXXXXXX

HKSC10XC XXXXXXXXXXXXXX

HKSC15XA XXXXXXXXXXX

HKSC15XB XXXXXXXXX XXXXX

HKSC15XF XXXXXXXX

HKSC19CA XXXX

HKSC19CB XXXXX

HKSC19CH X

HKSC20DA X

HKSC20DB XXX

HKSC20DH XX

HKSC20XF XXXX

HKSC25DA X

HKSC25DB X

25

PRODUCT DESIGN

This section gives a basic description of cooling unit opera­tion, its various components and their basic operation.
Ensure your system is properly sized for heat gain and loss
according to methods of the Air Conditioning Contractors
Association (ACCA) or equivalent.

CONDENSING UNIT

The condenser air is pulled through the condenser coil by a
direct drive propeller fan. This condenser air is then dis­charged out of the top of the cabinet. These units are
designed for free air discharge, so no additional resistance,
like duct work, shall be attached.

The suction and liquid line connections on present models
are of the sweat type for field piping with refrigerant type
copper. Front seating valves are factory installed to accept
the field run copper. The total refrigerant charge for a normal
installation is factory installed in the condensing unit.

ASXC, ASZC, DSXC, DSZC models are available in 2
through 5 ton sizes and use R-410A refrigerant. They are
designed for 208/230 volt single phase applications.

ASXC, ASZC, DSXC, DSZC R-410A model units use the
Copeland Scroll "Ultratech" Series compressors which are
specifically designed for R-410A refrigerant. These units also
have Copeland® ComfortAlert diagnostics. The Copeland
ComfortAlert diagnostics are integrated into the unitary (UC)
control. These models are ComfortNetTM ready.

There are a number of design characteristics which are
different from the traditional reciprocating and/or scroll com­pressors.

"Ultractech" Series scroll compressors will not have a dis­charge thermostat. Some of the early model scroll compres­sors required discharge thermostat.

"Ultratech" Series scroll compressors use "POE" or
polyolester oil which is NOT compatible with mineral oil
based lubricants like 3GS. "POE" oil must be used if
additional oil is required.

The ASXC [16 & 18], ASZC [16 & 18], DSXC [16 & 18] and
DSZC [16 & 18] series split system units use a two-stage
scroll compressor. The two-step modulator has an internal
unloading mechanism that opens a bypass port in the first
compression pocket, effectively reducing the displacement
of the scroll. The opening and closing of the bypass port is
controlled by an internal electrically operated solenoid.

The ZPS two-step modulated scroll uses a single step of
unloading to go from full capacity to approximately 67%
capacity. A single speed, high efficiency motor continues to
run while the scroll modulates between the two capacity
steps.

FIGURE A

A scroll is an involute spiral which, when matched with a
mating scroll form as shown, generates a series of crescent
shaped gas pockets between the two members.

During compression, one scroll remains stationary (fixed
scroll) while the other form (orbiting scroll) is allowed to orbit

®

(but not rotate) around the first form.

As this motion occurs, the pockets between the two forms
are slowly pushed to the center of the two scrolls while
simultaneously being reduced in volume. When the pocket
reaches the center of the scroll form, the gas, which is now
at a high pressure, is discharged out of a port located at the
center.

During compression, several pockets are being compressed
simultaneously, resulting in a very smooth process. Both the
suction process (outer portion of the scroll members) and the
discharge process (inner portion) are continuous.

Some design characteristics of the Compliant Scroll com­pressor are:

• Compliant Scroll compressors are more tolerant of liquid
refrigerant.

NOTE: Even though the compressor section of a Scroll
compressor is more tolerant of liquid refrigerant, contin­ued floodback or flooded start conditions may wash oil
from the bearing surfaces causing premature bearing
failure.

26

PRODUCT DESIGN

• Compliant scroll compressors perform "quiet" shutdowns
that allow the compressor to restart immediately without
the need for a time delay. This compressor will restart
even if the system has not equalized.

NOTE: Operating pressures and amp draws may differ
from standard reciprocating compressors. This informa­tion can be found in the unit's Technical Information
Manual.

CAPACITY CONTROL - COMFORTNET

TM

MODELS

During the compression process, there are several pockets
within the scroll that are compressing gas. Modulation is
achieved by venting a portion of the gas in the first suction
pocket back to the low side of the compressor thereby
reducing the effective displacement of the compressor. See
Figure A. Full capacity is achieved by blocking these vents,
increasing the displacement to 100%. A solenoid in the
compressor, controlled by an external 24-volt ac signal,
moves the slider ring that covers and uncovers these vents.
The vent covers are arranged in such a manner that the
compressor operates somewhere around 67% capacity
when the solenoid is not energized and 100% capacity when
the solenoid is energized. The loading and unloading of the
two step scroll is done “on the fly” without shutting off the
motor between steps. See Figure C below. The unloaded
mode default was chosen for two reasons:

Molded Plug*

Line

Run Capacitor

Line

Internal Unloader
Coil

24 vdc

*Rectifier is integrated on the UC PCB

FIGURE C

1. It is expected that the majority of run hours will be in the
low capacity, unloaded mode.

2. It allows a simple two-stage thermostat to control capac­ity through the second stage in both cooling and possibly
heating if desired.

18 to 28 volt ac. The coil power requirement is 20 VA. The
external electrical connection is made with a molded plug
assembly. This plug is connected to the Communicating
Unitary Control PCB (UC PCB) which contains a full wave
rectifier to supply direct current to the unloader coil.

COILS AND BLOWER COILS

MBVC blower cabinets are designed to be used as a two­piece blower and coil combination and can be utilized with the
CAUF, CAPF and CAPT coils for upflow and downflow
applications. The CACF and CHPF coils are designed for
horizontal applications. This two-piece arrangement allows
for a variety of mix-matching possibilities providing greater

flexibility.

The MBVC blower cabinets use a variable speed motor that
maintains a constant airflow with a higher duct static. MBVC
blower cabinets are approved for applications with cooling
coils of up to 0.8 inches W.C. external static pressure. The
MBVC models allow airflow trimming of +/-10%.

All units are constructed with R-4.2 insulation. In areas of
extreme humidity (greater than 80% consistently), insulate
the exterior of the blower with insulation having a vapor barrier
equivalent to ductwork insulation, providing local codes
permit.

AVPTC Multi-Position Air Handler

AVPTC is a multi-position, variable-speed air handler used
with R-410A and are available in 2 to 5 ton sizes with optional
3 kW to 25kW electric heat kits available for field installation.
The AVPTC unit’s blower design includes a variable-speed
ECM motor and is compatible with heat pumps and variable­capacity cooling applications.

This appliance can be installed in the vertical or left horizontal
position without modification. The horizontal right and downflow
positions require product modification. This product is de­signed for zero inches (0 inches) clearance; however, ad­equate access for service or replacement must be consid­ered without removing permanent structure. This unit can be
installed on a platform when deemed necessary.

In an attic installation a secondary drain pan must be provided
by the installer and placed under the entire unit with a
separate drain line properly sloped and terminated in an area
visible to the owner. This secondary drain pan is required in
the event that there is a leak or main drain blockage. Closed
cell insulation should be applied to the drain lines in uncon­ditioned spaces where sweating may occur.

UNLOADER SOLENOID

A nominal 24-volt direct current coil activates the internal
unloader solenoid. The input control circuit voltage must be

27

PRODUCT DESIGN

NOTE: AVPTC air handlers are factory-sealed to achieve a

2% or less leakage rate at 1.0" water gauge external duct
static pressure.

Communicating Unitary Control (UC) PCB

The Communicating System Unitary Control PCB is a micro­processor-based control for heat pump and air conditioning
condensing units with single-phase compressors up to 5 ton
capacity operating on standard residential or Delta and Wye
commercial power. The control incorporates the basic func­tionality of existing defrost controls, outdoor thermostats,
contactors, compressor staging controls, short cycle con­trols, line voltage monitors, Comfort Alert™ or CoreSense
Module (dependent upon which module you are using), two
speed condenser fan relays and the Active Protection com­ponent of enabled thermostats. The control is designed to
work as part of a fully communicating HVAC system with 4
wires. The control also supports legacy 24VAC thermostat
inputs for Y1, Y2, O and 24VAC outputs for RVS, W1, and L
for non-communicating systems. Outputs include compres­sor power, compressor stage select, and outdoor fan high
and outdoor fan low speed. System inputs include high/low
pressure switches, as well as thermistor inputs for outdoor
coil temperature and outdoor air temperature.

28

SYSTEM OPERATION

COOLING

The refrigerant used in the system is R-410A. It is a clear,
colorless, non-toxic and non-irritating liquid. R-410A is a
50:50 blend of R-32 and R-125. The boiling point at atmo­spheric pressure is -62.9°F.

A few of the important principles that make the refrigeration
cycle possible are: heat always flows from a warmer to a
cooler body. Under lower pressure, a refrigerant will absorb
heat and vaporize at a low temperature. The vapors may be
drawn off and condensed at a higher pressure and tempera­ture to be used again.

The indoor evaporator coil functions to cool and dehumidify
the air conditioned spaces through the evaporative process
taking place within the coil tubes.

NOTE: The pressures and temperatures shown in the
refrigerant cycle illustrations on the following pages are for
demonstration purposes only. Actual temperatures and pres­sures are to be obtained from the "Expanded Performance
Chart".

Liquid refrigerant at condensing pressure and temperatures,
(270 psig and 122°F), leaves the outdoor condensing coil
through the drier and is metered into the indoor coil through
the metering device. As the cool, low pressure, saturated
refrigerant enters the tubes of the indoor coil, a portion of the
liquid immediately vaporizes. It continues to soak up heat and
vaporizes as it proceeds through the coil, cooling the indoor
coil down to about 48°F.

Heat is continually being transferred to the cool fins and tubes
of the indoor evaporator coil by the warm system air. This
warming process causes the refrigerant to boil. The heat
removed from the air is carried off by the vapor.

As the vapor passes through the last tubes of the coil, it
becomes superheated. That is, it absorbs more heat than is
necessary to vaporize it. This is assurance that only dry gas
will reach the compressor. Liquid reaching the compressor
can weaken or break compressor valves.

The compressor increases the pressure of the gas, thus
adding more heat, and discharges hot, high pressure super­heated gas into the outdoor condenser coil.

In the condenser coil, the hot refrigerant gas, being warmer
than the outdoor air, first loses its superheat by heat trans­ferred from the gas through the tubes and fins of the coil. The
refrigerant now becomes saturated, part liquid, part vapor and
then continues to give up heat until it condenses to a liquid
alone. Once the vapor is fully liquefied, it continues to give up
heat which subcools the liquid, and it is ready to repeat the
cycle.

HEATING

The heating portion of the refrigeration cycle is similar to the
cooling cycle. By energizing the reversing valve solenoid coil,
the flow of the refrigerant is reversed. The indoor coil now
becomes the condenser coil, and the outdoor coil becomes
the evaporator coil.

The check valve at the indoor coil will open by the flow of
refrigerant letting the now condensed liquid refrigerant by­pass the indoor expansion device. The check valve at the
outdoor coil will be forced closed by the refrigerant flow,
thereby utilizing the outdoor expansion device.

COOLING CYCLE

For communicating room thermostat: When the room ther­mostat calls for either low stage cool or high stage cool,
appropriate commands are sent via the data 1 and data 2 lines
to the outdoor unit's UC control. The UC control energizes the
on-board compressor relay and the on-board outdoor fan
relay. The compressor high stage solenoid is energized if it
is a high stage call.

The UC control sends a fan command to the indoor unit (air
handler or furnace). The indoor unit operates the indoor
blower at the appropriate airflow level. The system operates
at the cooling level demanded by the thermostat.

When the thermostat is satisfied, appropriate commands are
sent to the UC control. The compressor relay and outdoor
fan relay is de-energized. The compressor high stage
solenoid is de-energized if it was energized. The UC control
sends an appropriate command to the indoor unit to de­energize the indoor blower motor.

If room thermostat fan status is set to be “on”, then indoor
blower would run continuously rather than cycling with the
compressor.

For heat pumps, the reversing valve is energized during the
cooling cycle. The call for cooling from the communicating
thermostat indicates to the control that the reversing valve is
to be energized during cooling operation.

HEATING CYCLE

For communicating room thermostat: When the room ther­mostat calls for either low stage heat or high stage heat,
appropriate commands are sent via the data 1 and data 2 lines
to the outdoor unit's UC control. The UC control energizes the
on-board compressor relay and the on-board outdoor fan
relay. The compressor high stage solenoid is energized if it
is a high stage call. The UC control sends a fan command
to the indoor unit (air handler or furnace). The indoor unit
operates the indoor blower at the appropriate airflow level.
The system operates at the cooling level demanded by the
thermostat.

When the thermostat is satisfied, appropriate commands are
sent to the UC control. The compressor relay and outdoor
fan relay is de-energized. The compressor high stage
solenoid is de-energized if it was energized. The UC control
sends an appropriate command to the indoor unit to de­energize the indoor blower motor.

29

SYSTEM OPERATION

DEFROST CYCLE - COMFORTNETTM MODELS

The defrosting of the outdoor coil is jointly controlled by the
UC PCB and the outdoor coil temperature (OCT) sensor.

The OCT sensor is clamped to a feeder tube entering the
outdoor coil. Defrost timing periods of 30, 60, 90 or 120
minutes may be selected via the dipswitch settings on the UC
PCB. In a communicating system, the defrost timing periods
can also be selected in the communicating thermostat user
menu. During operation, if the coil temperature is low enough
(approximately 31° F), the microprocessor will accumulate
the compressor run time. When the total compressor run
time reaches 30, 60, 90 or 120 minutes, and there is a call for
heat, the PCB will initiate a defrost cycle. When the
microprocessor detects the coil temperature to be high
enough (approximately 75 0F), or 10 minutes of maximum
defrost cycle time has elapsed, whichever occurs first, the
defrost cycle is terminated and the timing period is reset. The
field service personnel can also advance a heat pump to the
defrost cycle by simultaneously pressing the “TEST” button
and the “RECALL” button on the UC board.

Use the dipswitches to select defrost time interval (30, 60, 90
or 120 minutes) See chart below

30