Thermo Pride CMA4-50D36N Manual

THERMO PRODUCTS, LLC.
P.O. BOX 237
DENTON, NC 27239
PHONE: [phone]
MG-522
ECN 5580-MA 190515
MADE N USA
GAS FIRED HIGH EFFICIENCY FURNACE
DOWNFLOW & DIRECT VENT (SEALED COMBUSTION)
MODELS:
CMA4-50D3 N, CMA4-75D3 N
CMC2-50D3 N, CMC2-75D3 N
CMC2-50DV3N, CMC2-75DV3N
INSTALLATION AND SERVICE MANUAL
For installation in: Pour l'installation dans :
1. Manufactured Homes 1. Maisons fabriquées
2. Modular Homes/Buildings 2. Maisons modulaires / Bâtiments
3. Site Constructed—Residential 3. Site a construit - Résidentiel
(Single Story Dwellings) (Habitations à étage unique)
PLEASE READ THESE INSTRUCTIONS PRIOR TO INSTALLATION, INITIAL FIRING, AND BEFORE PERFORMING
ANY SERVICE OR MAINTENANCE. THESE INSTRUCTIONS MUST BE LEFT WITH THE USER AND SHOULD BE
RETAINED FOR FUTURE REFERENCE BY QUALIFIED SERVICE PERSONNEL.
VEUILLEZ LIRE CES INSTRUCTIONS AVANT L'INSTALLATION, LA MISE À FEU INITIALE ET AVANT TOUT
ENTRETIEN OU MAINTENANCE. CES INSTRUCTIONS DOIVENT ÊTRE LAISSÉES À L'UTILISATEUR ET DOIVENT
ÊTRE CONSERVÉES POUR RÉFÉRENCE ULTÉRIEURE PAR UN PERSONNEL DE MAINTENANCE QUALIFIÉ.

i
TABLE OF CONTENTS
LIST OF SECTIONS BEGINNING PAGE
I. SAFETY INFORMATION………………………………………………………...………… 1
II. FURNACE SPECIFICATIONS………………………………………………………......... 7
CMA4 series……………………………………………………………………………… 7
CMC2 series……………………………………………………………………………... 8
nstallation Parts Packages…………………………………………………………...... 10
III. GENERAL INSTRUCTIONS AND CLEARANCES…………………………..………… 11
IV. GENERAL INSTALLATION…………………………………………………..…………… 13
Furnace Location………………………………………………………………………… 13
Base nstallation………………………………………………………………………….. 15
Combustible Floor Base…………………………………………………………….. 15
Cottage Base……………………………………………………………………….… 16
Alcove nstallation………………………………………………………………………... 17
Closet nstallation………………………………………………………………………… 17
Fuel Piping………………………………………………………………………………... 19
General Venting Requirements………………………………………………………… 20
Connecting Exhaust Vent and Combustion Air ntake……………………………….. 22
Direct Venting Through a Sidewall…………………………………………………….. 24
Vent and Combustion Air Pipes……………………………………………………. 24
Exhaust Vent Termination Elbow……………………………………………….…. 24
Exhaust Vent Terminal Location Clearance Requirements…………………..…. 25
Vent Terminal Location Guidelines………………………………………………… 27
nstallation of Outside Exhaust/ ntake Terminations………………….……………… 27
Connecting the Furnace to Roof Vent/ ntake Terminations ……………...………… 28
Condensate Drain Line and Trap Assembly…………………………………………... 30
Electrical Wiring………………………………………………………………………….. 31
Electrical Branch Supply Circuit……………………………………………………. 31
Connection of Power Supply Wires………………………………………………... 31
Connection of Room Thermostat Wires…………………………………………… 31
Blower Motor Speed Wiring……………………………………………………….... 33
Field and Replacement Wiring…………………………………………………...… 40
V. STARTING THE UNIT……………………………………………………………..………. 41
Sequence of Operations………………………………………………………………… 41
nitial Start Up…………………………………………………………………………..… 43
Adjustment of BTU nput Rate…………………………………….…………………..... 44
Burner Adjustment……………………………………………………………………….. 45
Setting Temperature Rise…………………………………………………….…………. 46
Furnace Check-out Procedure……………………………………….….……………. 47
VI. INSTALLER'S INSTRUCTIONS TO USER…………………………………………….... 48
VII. DEALER MAINTENANCE…………………………………………………………...…….. 48
Electrical………………………………………………………………………………….. 49
General nspection………………………………………………………………………. 49
Vent Pipe, Combustion Air ntake…………………………………………………. 49
Condensate Line/Trap Assembly………………………………………………..… 49
Burners……………………………………………………………………………….. 49
nducer Blower Assembly……………………………………………………..……. 49
Gasket/Sealing Materials…………………………………………………….……... 50
Heat Exchanger………………………………………………………………………….. 50
Cleaning the Coil Air Side………………………………………………………..…. 50

ii
House Air Blower………………………………………………………………………… 50
Return Air Filter…………………………………………………………………………... 50
Filter Maintenance Procedure……………………………………………………… 51
Filter Replacement…………………………………………………………………... 51
VIII. TROUBLE SHOOTING…………………………………………………………………... 51
Diagnostic Features……………………………………………………………………… 52
Troubleshooting Guide…………………………………………………………………... 53
APPENDIX-A REPLACEMENT PARTS……………………………………………… 57
APPENDIX-B WIRING DIAGRAM…………………………………………………….. 1
LIST OF FIGURES
Combustible Floor Base……………………………………………………………..…………... 13
Coil Cabinets………………………………………………………………………………………. 14
Cottage Base………………………………………………………………………...……………. 14
Combustible Floor Base Cutout……………………………………………..………………….. 15
Connector Duct nstallation……………………………………………………………………… 15
Alcove nstallation Clearances………………………………………………...………………… 17
Closet nstallation Clearances…………………………………………………….…………….. 18
Exhaust Vent and Combustion Air ntake Connections………………………………………. 22
Top Front Access Panel……………………………………………………………………….…. 23
Direct Vent Terminations…………………………………………………………….………….. 24
Relative Locations of Direct Vent Terminations When Sidewall Venting…………………… 25
Minimum Clearances Between Vent Terminal and Various Building Features………...….. 26
Construction Details of Sidewall Vent and Air ntake Terminations………….……..………. 28
Construction Details of Vertical Vent and Air ntake Terminations………….………………. 29
Vertical Vent Using Slope Adapter…………………………………………………...…………. 29
Venting Through Ceiling…………………………………………………………………….…… 30
Condensate Drain Line and Trap Assembly…………………………………………………… 30
Blower Motor Speed Wiring……………………………………………………………….…….. 33
Burner Flame Adjustment…………………………………………………………………...…… 46
LIST OF TABLES
Minimum Clearances…………………………………….…………………………..…………… 12
Maximum Vent Length……………………………………………………………..…………….. 21
Maximum Recommended Thermostat Wire Length…………………………………….…….. 32
Gas Pressure Chart……………………………………………………………………….……… 45
REFERENCED PUBL CAT ONS: FOR COP ES CONTACT:
NAT ONAL FUEL GAS CODE NAT ONAL F RE PROTECT ON ASSOC AT ON
NFPA 54/ANS -Z233.1 1 BATTERYMARCH PARK
(LATEST ED T ON) P.O. BOX 9101
QU NCY, MA 02269-9101

iii
c WARNING: f the information in these instructions is not followed exactly, a fire or explosion
may result causing property damage, personal injury, or loss of life.
c AVERTISSEMENT: Si les informations contenues dans ces instructions ne sont pas suivies
à la lettre, un incendie ou une explosion pourrait en résulter, causant des dommages matériels,
des blessures corporelles ou la mort.
c WARNING: mproper installation, adjustment, service, or maintenance can cause injury or
property damage. Refer to this manual. For assistance or additional information, consult a
qualified installer, service agency, or fuel supplier.
c AVERTISSEMENT: Une installation, un réglage, un entretien ou une maintenance incorrects
peuvent provoquer des blessures ou des dommages matériels. Reportez-vous à ce manuel.
Pour obtenir de l'aide ou des informations supplémentaires, consultez un installateur qualifié,
une agence de service ou un fournisseur de carburant.
c WARNING: Do not use this appliance if any part has been underwater. mmediately call a
qualified service technician to inspect the appliance and to replace any part of the electrical or
control system that has been underwater.
c AVERTISSEMENT: N'utilisez pas cet appareil si une pièce a été immergée. Appelez
immédiatement un technicien qualifié pour inspecter l'appareil et remplacer toute pièce du
système électrique ou de commande sous l'eau.

1
I. SAFETY INFORMATION
This and the following page contain reproductions of the various warning and instruction
labels placed on the Thermo Pride Condensing Gas Furnaces. Please read and comply
with the contents of these labels.

2
This and the previous page contain reproductions of the various safety and instruction
labels placed on the Thermo Pride Condensing Gas Furnaces. Please read and comply
with the contents of these labels.

3
This and the previous page contain reproductions of the various safety and instruction
labels placed on the Thermo Pride Condensing Gas Furnaces. Please read and comply
with the contents of these labels.

4
The following safety information should be read, understood, and followed by the
installer.
1. Use only with type of gas approved for this furnace. Refer to furnace rating plate.
2. Do not install this furnace where it could be exposed to drafts or other wind or
moisture conditions. Refer to Section V of this manual.
3. Provide adequate ventilation air to the furnace space. Refer to Section V, C and D,
of this manual.
4. Connect this furnace to an approved vent system only. Combustion products must
be carried outdoors. Refer to Section V, F thru J, of this manual.
5. Never test for gas leaks with an open flame. Leak test methods must comply with
State, Local and National codes including the National Fuel Gas Code NFPA 54/ANS -
Z233.1 (Latest Edition).
6. Always install furnace with a duct system that has an external static pressure within
the allowable range referenced in specifications.
7. Make sure supply air ducts are completely sealed to the furnace casing. Refer to
Section V.
The following pages contain various warnings and cautions found throughout the
Thermo Pride Gas Fired High Efficiency Furnace Manual. Please read and comply
with the statements below.
: This furnace is not to be used for temporary heating of buildings or
structures under construction.
: These high efficiency condensing furnaces are not certified for and
shall not be vented into a standard or any type of chimney.
: Negative pressure inside the closet with closet door closed and the
furnace blower operating on high speed shall be no more negative than minus
0.05 inch water column.
: Do not obstruct any return air openings, including the return grille on
the furnace. To do so may cause the furnace to activate the high limit and shut
down.

5
: The vent and air intake elbows must be kept away from bushes,
shrubs or any vegetation that may restrict the flow of flue products. t must also
be kept clear of any leaves, weeds or other combustible materials. Keep the vent
hood clear of snow. Avoid locating the terminals in areas where standing water or
condensate drippage may be a problem.
: This CMA/CMC furnace has been designed to be installed as a direct
vent system and must have its combustion air brought in from outside the
conditioned space. The failure to install the vent/air intake system as specified in
these instructions will void the heat exchanger warranty and may result in
property damage, personal injury or loss of life.
: Outside combustion air must not come from an area that is directly
adjacent to a pool, hot tub or spa. Measures should be taken to prevent the entry
of corrosive chemicals or vapors to the combustion and ventilation air supply.
Such chemicals include but are not limited to chlorinated and/or fluorinated
hydrocarbons such as found in refrigerants, aerosol propellants, dry cleaning
fluids, degreasers and removers. Other harmful compounds may come from
bleaches, air fresheners or mastics. Vapors from such products can form acid
compounds when burned in a gas flame. Should acid compounds form in your
furnace, it may reduce the life of the furnace.
: Because of the potential of odorant fade, a gas leak may not be
detected by smell. f this furnace is installed below grade, contact your gas
supplier for a gas detector.
: All gas piping must be leak tested methods approved by State, Local
and National Codes including the National Fuel Gas Code NFPA 54/ANS -Z233.1
(Latest Edition). A final test for gas leakage must be made after purging the gas
line. This test must be conducted with the unit operating and should include the
furnace piping and gas valve. Never use an open flame to check for a gas leak.
: Care must be taken not to wet electronic components during leak test.
Wetting the primary ignition module may damage its circuitry and cause a
hazardous situation. Dry moisture from all leads and terminals if wetting occurs.
Wait at least 24 hours for the circuit to fully dry before energizing the burner
circuit.
: The furnace and its individual gas shutoff valve must be disconnected
from the gas supply during pressure testing of the gas supply system at
pressures in excess of 1/2 PS G or 14.0" w.c. The furnace must be isolated from
the gas supply by closing its manual shut off valve at test pressures equal to or
greater than 1/2 PS G or 14.0" w.c.

6
: Copper and brass tubing and fittings (except tin lined) shall not be
used if the gas contains more than a trace (0.3 grains per 100 cubic ft.) of
hydrogen sulfide gas. Check with your gas supplier.
: TURN OFF THE ELECTR CAL POWER to the furnace before attempting
to change blower speed wiring.
: Turn off power to furnace before it is placed into service. The gas
piping system must have been leak tested by a qualified heating contractor in
accordance with State, Local and National Codes including the National Fuel Gas
Code NFPA 54/ANS -Z233.1 (Latest Edition).
: t may be necessary to purge the air out of the gas line for initial start-
up of the furnace after installation. This should be done by a qualified heating
contractor. f excessive gas escapes when purging the gas supply at the union,
allow the area to ventilate for at least 15 minutes before attempting to start the
furnace. LP gas is especially dangerous because the specific gravity of LP gas
allows it to accumulate at floor level at a dangerous concentration.
: Heat exchanger oil will burn off on initial firing creating an unpleasant
odor. To prevent this odor from occurring more than once, it is suggested that:
1. A window(s) be opened.
2. The thermostat set at highest setting.
3. The furnace remain running at conditions 1&2 above for 15 minutes or until
odor has dissipated.
: The CMA/CMC furnace models are of direct vent design and do not
require an air shutter adjustment (air shutters are not used) for proper flame
characteristics. Burner box access cover must always be secured with all screws
in place and tightened before operating furnace.
: Personal injury or property damage could result from repair or service
of this furnace by anyone other than a qualified heating contractor.
: Label wires prior to disconnection when servicing controls. Wiring
errors can cause improper and dangerous operation.
: The inducer motor mounting plate gasket and the collector box gasket
must be replaced if they show any sign of having been damaged.
: Power must be disconnected before servicing.

7
II. FURNACE SPECIFICATIONS
MODEL CMA4-50D3 CMA4-75D3
NPUT N BTUH 50,000 75,000
OUTPUT N BTUH 48,000 72,000
MA N OR F CE-NAT. #42
MA N OR F CE-LP #54
GAS SUPPLY PRESSURE
L.P. M N MUM 11” N.W.C.
NAT. M N MUM 4.5” N.W.C.
L.P. MAX MUM 14” N.W.C.
NAT. MAX MUM 14” N.W.C.
GAS MANIFOLD PRESSURE
L.P. 10.0” + 0.3 N.W.C.
NAT. 3.5” + 0.3 N. W.C.
NTAKE S ZE N NCHES 2”
VENT S ZE N NCHES 2”
NOM NAL TEMPERATURE R SE 55°F 65°F
SEASONAL EFF C ENCY (AFUE*) 95%
*ANNUAL FUEL UT L ZAT ON
EFF C ENCY
DIMENSIONS
CAB NET S ZE W DTH 18” DEPTH 25-3/4" HE GHT 57"
SUPPLY A R OUTLET W DTH 12” DEPTH 12"
ELECTR CAL SUPPLY 115 VOLTS-- 60HZ --1/PH
FUSE OR HACR BREAKER 15 AMPS
TOTAL CURRENT AMPS 7.15 AMPS
NOM NAL ANT C PATOR SETT NG 0.8 M LL AMPS
F LTER S ZE (1) 18” X 24” X 1”
APPROX MATE SH PP NG WE GHT 175 LBS. 185 LBS.
BLOWER DATA
BLOWER MODEL 12-9T D RECT DR VE
MOTOR HORSEPOWER 1/2 PSC
MOTOR RPM 1065 (H GH SPEED)
CFM @ .2 & .5 N. W.C. SPEED .2” .5” | .2” .5”
LOW 805 695 | 797 668
MD-LOW 1010 860 | 995 869
MD-H GH 1196 1038 | 1210 1076
H GH 1338 1162 | 1420 1259
FOR BURNER COMBUST ON NFORMAT ON REFER TO N T AL STARTUP.

8
MODEL CMC2-50D3 CMC2-75D3
NPUT N BTUH 50,000 75,000
OUTPUT N BTUH 48,000 72,000
MA N OR F CE-NAT. #42
MA N OR F CE-LP #54
GAS SUPPLY PRESSURE
L.P. M N MUM
11” N.W.C.
NAT. M N MUM
4.5” N.W.C.
L.P. MAX MUM 14” N.W.C.
NAT. MAX MUM 14” N.W.C.
GAS MANIFOLD PRESSURE
L.P. 10.0” + 0.3 N.W.C.
NAT. 3.5” + 0.3 N. W.C.
NTAKE S ZE N NCHES
2”
VENT S ZE N NCHES 2”
NOM NAL TEMPERATURE R SE 55°F 65°F
SEASONAL EFF C ENCY (AFUE*) 95%
*ANNUAL FUEL UT L ZAT ON
EFF C ENCY
DIMENSIONS
CAB NET S ZE W DTH 18-3/4” DEPTH 25-3/4" HE GHT 76-1/8"
SUPPLY A R OUTLET W DTH 12” DEPTH 12"
ELECTR CAL SUPPLY 115 VOLTS-- 60HZ --1/PH
FUSE OR HACR BREAKER 15 AMPS
TOTAL CURRENT AMPS 7.15 AMPS
NOM NAL ANT C PATOR SETT NG 0.8 M LL AMPS
F LTER S ZE (1) 18” X 24” X 1”
APPROX MATE SH PP NG WE GHT 195 LBS. 205 LBS.
BLOWER DATA
BLOWER MODEL 12-9T D RECT DR VE
MOTOR HORSEPOWER 1/2 PSC
MOTOR RPM 1065 (H GH SPEED)
CFM @ .2 & .5 N. W.C. SPEED .2” .5” | .2” .5”
LOW 805 695 | 797 668
MD-LOW 1010 860 | 995 869
MD-H GH 1196 1038 | 1210 1076
H GH 1338 1162 | 1420 1259
FOR BURNER COMBUST ON NFORMAT ON REFER TO N T AL STARTUP.

9
MODEL CMC2-50DV3 CMC2-75DV3
NPUT N BTUH 50,000 75,000
OUTPUT N BTUH 48,000 72,000
MA N OR F CE-NAT. #42
MA N OR F CE-LP #54
GAS SUPPLY PRESSURE
L.P. M N MUM
11” N.W.C.
NAT. M N MUM
4.5” N.W.C.
L.P. MAX MUM 14” N.W.C.
NAT. MAX MUM 14” N.W.C.
GAS MANIFOLD PRESSURE
L.P. 10.0” + 0.3 N.W.C.
NAT. 3.5” + 0.3 N. W.C.
NTAKE S ZE N NCHES
2”
VENT S ZE N NCHES 2”
NOM NAL TEMPERATURE R SE 55°F 65°F
SEASONAL EFF C ENCY (AFUE*) 95%
*ANNUAL FUEL UT L ZAT ON
EFF C ENCY
DIMENSIONS
CAB NET S ZE W DTH 18-3/4” DEPTH 25-3/4" HE GHT 76-1/8"
SUPPLY A R OUTLET W DTH 12” DEPTH 12"
ELECTR CAL SUPPLY 115 VOLTS-- 60HZ --1/PH
FUSE OR HACR BREAKER 15 AMPS
TOTAL CURRENT AMPS 7.15 AMPS
NOM NAL ANT C PATOR SETT NG 0.8 M LL AMPS
F LTER S ZE (1) 18” X 24” X 1”
APPROX MATE SH PP NG WE GHT 195 LBS. 205 LBS.
BLOWER DATA
BLOWER MODEL 12-9T D RECT DR VE
MOTOR HORSEPOWER 1/2 ECM
MOTOR RPM 1075 (H GH SPEED)
CFM @ .2 & .5 N. W.C. SPEED .2” .5” | .2” .5”
LOW 639 437 | 935 802
MD-LOW 834 653 | 998 880
MED 948 811 1113 1007
MD-H GH 1145 1026 | 1177 1083
H GH 1365 1265 | 1272 1177
FOR BURNER COMBUST ON NFORMAT ON REFER TO N T AL STARTUP.

10
INSTALLATION PARTS PACKAGES
PARTS PKG#
DESCR PT ON
CMA4-50D36N CMA4-75D36N
S00S4248 S00S4249
PART # QTY PART # QTY
J-box cover 350020 1 350020 1
Wire nut 300132 2 300132 2
3" stainless steel hose clamp 300276 4 300276 4
2-3/8" radiator hose 410017 2 410017 2
CPVC adapter 320833 1 320833 1
LP conversion kit AOPS7741 1 AOPS7742 1
PARTS PKG#
DESCR PT ON
CMC2-50D36N CMC2-75D36N
S00S4190 S00S4191
PART # QTY PART # QTY
J-box cover 350020 1 350020 1
Wire nut 300132 2 300132 2
3" stainless steel hose clamp 300276 4 300276 4
2-3/8" radiator hose 410017 2 410017 2
CPVC adapter 320833 1 320833 1
LP conversion kit AOPS7741 1 AOPS7742 1
Gasket, drain knock-out 330355 1 330355 1
Grommet, vinyl 3/8" 350040 1 350040 1
Grommet, vinyl 7/8" 350009 1 350009 1
Screw, #8 x 1/2 Tek 300208 6 300208 6
Coil trim panel 619113 1 619113 1
Bushing, UB-875 350750 1 350750 1
Bushing, SR-34-2 350016 1 350016 1
PARTS PKG#
DESCR PT ON
CMC2-50DV3N CMC2-75DV3N
S00S4244 S00S4245
PART # QTY PART # QTY
J-box cover 350020 1 350020 1
Wire nut 300132 2 300132 2
3" stainless steel hose clamp 300276 4 300276 4
2-3/8" radiator hose 410017 2 410017 2
CPVC adapter 320833 1 320833 1
LP conversion kit AOPS7741 1 AOPS7742 1
Gasket, drain knock-out 330355 1 330355 1
Grommet, vinyl 3/8" 350040 1 350040 1
Grommet, vinyl 7/8" 350009 1 350009 1
Screw, #8 x 1/2 Tek 300208 6 300208 6
Coil trim panel 619113 1 619113 1
Tape, aluminum 2" 390111 42" 390111 42"
Bushing, UB-875 350750 1 350750 1
Bushing, SR-34-2 350016 1 350016 1

11
III. GENERAL INSTRUCTIONS AND CLEARANCES – READ BEFORE START OF
INSTALLATION
1. The BTU output capacity of the furnace proposed for installation should be based
on a heat loss calculation made according to the manuals provided by the Air
Conditioning Contractors of America (ACCA) or the American Society of Heating,
Refrigeration and Air Conditioning Engineers, nc. (ASHRAE).
2. This furnace is equipped with orifices sized for operation with natural gas. For
conversion to Propane Gas see instruction MG-815 in Gas Conversion Kit provided
with furnace.
3. These Category Type V furnaces are shipped completely assembled and wired
(internally). See the Dealer Receiving and Freight Claim Procedure Section of the
price guide for parts shortage or damage. The furnace and duct system must be
adjusted to obtain a temperature rise of 40°F to 70°F through the furnace after
installation for the 50 series and 50°F to 80°F for the 75 series. (See rating label
located on separator panel inside the furnace vestibule). The return air temperature
must be above 55°F to prevent condensation of flue products in the primary heat
exchanger. The installation must conform with local codes, or in the absence of local
codes, with the National Fuel Gas Codes (ANS Z223.1 or latest edition) and with
these instructions.
: This furnace is not to be used for temporary heating of buildings or
structures under construction.
Many of the chemicals used during construction, when burned, form acid bearing
condensate that can substantially reduce the life of the heat exchanger.
4. t is recommended that a commercially available CO alarm be installed in
conjunction with any fossil fuel burning appliance. The CO alarm shall be installed
according to the alarm manufacturer’s installation instructions and be listed in
accordance with the latest edition of the UL Standard for Single and Multiple Station
Carbon Monoxide Alarms, UL 2034, or the CSA nternational Standard, Residential
Carbon Monoxide Alarming Devises, CSA 6.19.
5. The installer shall be familiar with and comply with all codes and regulations
applicable to the installation of these heating appliances and related equipment. n
lieu of local codes, the installation shall be in accordance with the current provisions
of one or more of the following standards.
a. Federal Manufactured Home Constructions & Safety Standard (H.U.D. Total
24, Part 280.)

12
b. American National Standard (ANS -119.2/NFPA-501C) for all recreational
vehicle installations.
c. American National Standard (ANS -Z223.1/NFPA-54) for all gas-fired
furnaces.
d. American National Standard (ANS -C1/NFPA-70 Electric Code for all
electrical field wiring.
e. These gas-fired units are in compliance with ANS Z 21.47 CAN/CGA Z223-
2001 Central Furnace test standard.
f. These gas-fired units have been listed by ETL “For installation as central
furnace special type for single story dwelling.”
: The area around the furnace must be kept free and clear of
combustible materials, especially papers and rags.
: This furnace is not to be used as a construction heater.
Listed below are definitions of “ COMBUSTIBLE MATERIAL” and “NON-
COMBUSTIBLE MATERIAL.”
COMBUSTIBLE MATERIAL:
Material made of or surfaced with wood, compressed paper, plant fibers, plastics or
other material that will ignite.
NON-COMBUSTIBLE MATERIAL:
Material that will not ignite and burn. Such materials consist entirely of steel, iron, brick,
tile, concrete, slate, glass or a plaster combination thereof.
MODELS
CMA4
/
CMC2
CLOSET ALCOVE
FRONT
BACK
S DES
VENT CONNECTOR(PVC)
TOP
PLENUM S DES
TOP AND S DES OF DUCT
BOTTOM OF DUCT
0” *
0”
0”
0”
0”
1”
1”
1”
18”
0”
0”
0”
0”
1”
1”
1”
Table 1
* See pages 17, 18 & Figure 5 for explanation of clearances.
This heating appliance must be installed with clearances not less than the minimums
shown above as well as ample clearance for easy access to the air filter, blower
assembly, burner assembly, controls, and vent connections.

13
IV. GENERAL INSTALLATION
A. FURNACE LOCATION
1. For best performance, locate the furnace so that it is centralized with respect
to the duct system.
2. The furnace installation is only intended for free air return through the furnace
door louvers. DO NOT connect a ducted return air system directly to the furnace.
An improper return air installation may create a hazard and damage equipment,
as well as void all warranties.
3. Model CMA4 furnace may be installed on a combustible floor when utilizing
either the No. 70 counterflow floor base or CE111S coil cabinet for below the
floor duct systems, or the cottage base for floor level air distribution. See Figure
1A for description of Combustible Floor Base and Figure 1C for Cottage Base.
4. Model CMC2 furnace is designed to be installed directly on a combustible
floor and is not required to be installed on a base.
This furnace is ETL listed for closet, alcove or free standing applications. All
applications must comply with the requirements of this manual.
Combustible Floor Base Model: 70-BASE
For CMA4 models only.
Figure 1A.

14
Coil Cabinet Model: CE111S
Note: Coil cabinet cannot be utilized as a cottage base.
CE111S
Figure 1B.
Cottage Base Model: 01COT-BASE
For CMA4 models only.
NOTE: Serves as a plenum for single story applications with exposed supply air
systems.

15
Figure 1C.
B. BASE INSTALLATION – CMA4 models only
1. Combustible Floor Base Model: 70 BASE (for CMA4 models only)
Use the base bottom panel as a template to mark floor opening locations (see
Figure 2). Cut a square opening in the floor for the supply air connector duct. Cut
the opening 1-inch larger than the square template opening. (duct requires 1-inch
clearance to combustible floor).
Figure 2.
Figure 3.