Model and Manufacturing numbers listed on page 4. Service Instructions 40" 90% Condensing Gas Furnaces GUCA, GCCA & Accessories This manual is to be used by qualified HVAC technicians only. Amana does not assume any responsibility for property damage or personal injury for improper service procedures done by an unqualified person.
INDEX Important Safety Information ................................................................................. 3 Product Identification ............................................................................................. 4-13 Furnace Specifications .......................................................................................... 14-15 Blower Performance Specifications ....................................................................... 16-18 Combustion and Ventilation Air ........
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.
PRODUCT IDENTIFICATION The model and manuacturing number are used for positive identification of component parts used in manufacturing. At which time engineering and manufacturing changes take place where interchangeability of components are affected, the manufacturing number will change. It is very important to use the model and manufacturing numbers at all times when requesting service or parts information.
PRODUCT IDENTIFICATION G U C A 045 A X 30 Product Type Airflow Capability 30: 3.0 Tons G: Gas Furnace 35: 3.5 Tons 40: 4.0 Tons Supply Type C: Counterflow/Horizontal U: Upflow/Horizontal 50: 5.0 Tons Additional Features A: Not NOx Certified Furnace Type C: Condensing (90%) X: NOx Models Design Series A: First Series Model Family A: Air Command 90 (40" Height) Nominal Input 045: 46,000 Btuh 070: 69,000 Btuh 090: 92,000 Btuh 115: 115,000 Btuh 5 Rev.
PRODUCT IDENTIFICATION FOR YOUR SAFETY READ BEFORE OPERATING LIRE AVANT DE METTRE EN MARCHELIRE WARNING: If you do not follow these instructions explosion may result causing property damage, personal injury or loss of life. AVERTISSEMENT: Quiconque ne respecte pas á la lettre les instructions dans le présent manuel risque de déclecher un incendie ou une explosion entraînant des dammages matériels, des lésions corporelles ou la perte de vies humaines. A. This appliance does not have a pilot.
PRODUCT IDENTIFICATION GUCA AIR DISCHARGE A 28 3/4 3/4 2 1/2 20 3/16 AIR INTAKE PIPE 2" PVC ALTERNATE GAS SUPPLY HOLE LEFT SIDE DRAIN LINE HOLES 14 VENT/FLUE PIPE 2" PVC 2 1/16 DRAIN TRAP CL 30 1/4 CONDENSATE DRAIN TRAP w/ 3/4" PVC DISCHARGE (RIGHT OR LEFT SIDE) 40 27 1/8 19 3/16 SIDE CUT-OUT 2 5/8 19 3/16 2 1 3/4 ALTERNATE VENT/FLUE LOCATION 4 1/8 6 1/8 30 1/4 23 LOW VOLTAGE ELECTRICAL HOLE HIGH VOLTAGE ELECTRICAL HOLE ALTERNATE AIR INTAKE LOCATION STANDARD GAS SUPPLY HOLE 2 11/16
PRODUCT IDENTIFICATION GCCA A 28 3/4 3/4 2 1/2 20 1/4 3/4 B (RETURN) C 3/4 AIR INTAKE PIPE 2" PVC 2 1/16 1 3/4 HIGH VOLTAGE ELECTRICAL HOLE CONDENSATE DRAIN TRAP w/ 3/4" PVC DISCHARGE (RIGHT OR LEFT SIDE) 40 28 5/16 2 5/8 HIGH VOLTAGE ELECTRICAL HOLE 1 3/4 LOW VOLTAGE ELECTRICAL HOLE LEFT SIDE DRAIN LINE HOLES VENT/FLUE PIPE 2" PVC DRAIN TRAP CL LOW VOLTAGE ELECTRICAL HOLE ALTERNATE AIR INTAKE LOCATION 2 11/16 DRAIN 19 7/8 TRAP CL 32 3/16 ALTERNATE VENT/FLUE LOCATION 6 1/8 28 5/16
PRODUCT IDENTIFICATION 7 8 7 5 9 10 26 10 27 34 4 3 25 3 1 33 16 17 18 19 20 18 32 24 3 22 16 3 20 21 31 23 19 32 29 30 12 13 14 15 2 15 33 30 23 28 24 27 26 25 Upflow/Horizontal (GUCA Models) 17 12 18 19 18 19 22 31 29 11 11 BLOWER COMPARTMENT 6 20 20 14 13 2 21 BURNER COMPARTMENT BLOWER COMPARTMENT BURNER COMPARTMENT 5 1 9 7 8 7 6 4 Counterflow/Horizontal (GCCA Models) 1 Gas Valve 17 Induced Draft Blower 2 Gas Line Entrance (Alternate) 18
PRODUCT IDENTIFICATION A large array of Amana coils are available for use with the new GUCA and GCCA furnaces, in either upflow, counterflow, or horizontal applications. These coils are available in both cased and uncased models, with or without a TXV expansion device. These new 90%+ furnaces match up with the existing Amana coils as shown in the chart below.
Furnace Furnace Front PRODUCT IDENTIFICATION ACCESSORIES Floor Base Gasket Floor 2" 1" Min. Plenum Plenum Duct D 3/4" C B Side View Floor Base Part Numbers Used On Models CFB16 Floor Opening H J Plenum Size K L GCCA045__30 GCCA070__30 16-1/2 23-3/4 15 18-9/16 CFB20 GCCA070__40 GCCA090__40 20-1/2 23-3/4 19 18-9/16 CFB24 GCCA090__50 GCCA115__50 24-1/2 23-3/4 23 18-9/16 B A F G E 3/4" A 4-7/16" 3/4" F E Front View All dimension are in inches.
PRODUCT IDENTIFICATION ACCESSORIES MAC1 SPECIFICATIONS 600-2000CFM CAPACITY MEDIA SERVICE LIFE 12 MO.NOMINAL UL CLASS 2 MEDIA LISTING DIMENSIONS 7-1/4 A 25 B 22-1/8 C D 22-5/8 17-11/16 E RESISTANCE CFM INCHES W.C. 600 .04 .05 800 .09 1000 .12 1200 1400 .15 .18 1600 .22 1800 .27 2000 A B All dimensions are in inches. C E MEDIA AIR CLEANER Used On Models GUCA GUCA D MEDIA AIR CLEANER EAC5 SPECIFICATIONS 2000 CFM (3400 RATED CAPACITY .13 in. w.g. @ MAX. PRESSURE DROP (2) 12 lbs.
PRODUCT IDENTIFICATION ACCESSORIES Vertical (VCVK) Horizontal (HCVK) Combustion Air Intake Pipe Outside Connection for Fresh Air Intake Pipe to Furnace Vent/Flue Termination with Tee Vent/Flue Termination (Tee, Pipe, & 2" to 4" Reducer) Combustion Air Intake Pipe Seal Penetration with Caulking Tee 12" Minimum Above Roof or Highest Anticipated Snow Level 12" Minimum Above Grade or Highest Anticipate Snow Level Inside Connection for Vent/Flue Pipe from Furnace Pipe to Furnace Outside Wall Thickn
FURNACE SPECIFICATIONS MODEL GUCA045AX30 GUCA070AX30 GUCA070AX40 GUCA090AX40 GUCA090AX50 GUCA115AX50 Btuh Input (US) 46,000 69,000 69,000 92,000 92,000 115,000 Output (US) 42,800 64,400 64,400 86,000 85,300 106,500 Input (CAN) 46,000 69,000 69,000 92,000 90,000 115,000 Output (CAN) 42,800 64,400 64,400 86,000 85,300 106,500 92.0% 92.0% 92.0% 92.0% 92.0% 92.0% Rated External Static (WC) .20 - .50 .20 - .50 .20 - .50 .20 - .50 .20 - .50 .20 - .
FURNACE SPECIFICATIONS MODEL GCCA045AX30 GCCA070AX30 GCCA070AX40 GCCA090AX40 GCCA090AX50 GCCA115AX50 Btuh Input (US) 46,000 69,000 69,000 92,000 92,000 115,000 Output (US) 43,000 65,400 63,300 87,500 86,200 109,100 Input (CAN) 46,000 69,000 69,000 92,000 92,000 115,000 Output (CAN) 43,000 65,400 63,300 87,500 86,200 109,100 92.0% 92.0% 92.0% 92.0% 92.0% 92.0% Rated External Static (WC) .20 - .50 .20 - .50 .20 - .50 .20 - .50 .20 - .50 .20 - .
BLOWER PERFORMANCE SPECIFICATIONS GUCA Blower Performance Model Heating Speed As Shipped ( ) External Static Pressure (Inches Water Column) Tons AC Motor Speed at 0.5" 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 ESP CFM RISE CFM RISE CFM RISE CFM RISE CFM RISE CFM CFM CFM HIGH 3.0 1322 --- 1298 --- 1278 --- 1243 --- 1196 --- 1137 1074 1000 GUCA045AX30 MED 2.5 1131 35 1114 35 1097 36 1068 37 1019 39 968 907 827 (MED-LO) MED-LO 2.
BLOWER PERFORMANCE SPECIFICATIONS GUCA Blower Performance Model Heating Speed As Shipped ( ) External Static Pressure (Inches Water Column) Tons AC Motor Speed at 0.5" 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 ESP CFM RISE CFM RISE CFM RISE CFM RISE CFM RISE CFM CFM CFM HIGH 3.0 1327 ----- 1342 ----- 1305 ----- 1251 ----- 1195 ----- 1128 1056 969 GCCA045AX30 MED 2.5 1195 ----- 1179 ----- 1136 35 1092 36 1037 38 988 918 839 (MED-LO) MED-LO 2.
BLOWER PERFORMANCE SPECIFICATIONS 18 Rev.
COMBUSTION AND VENTILATION AIR (DIRECT/NON-DIRECT VENT MODELS) WARNING Property damage, bodily injury, or death may occur if the furnace and any other fuel-burning appliances are not provided with enough fresh air for proper combustion and ventilation of flue gases. Most homes require outside air to be supplied into the furnace area.
COMBUSTION AND VENTILATION AIR (DIRECT/NON-DIRECT VENT MODELS) 2. When communicating with the outdoors through vertical ducts, each opening shall have a minimum free area of 1 square inch per 4,000 BTU per hour of total input rating of all equipment in the enclosure. The following drawing illustrates the air opening specifications for equipment located in confined spaces; all air from outdoors through ventilated attic. Equipment Located in Confined Spaces; All Air from Inside Building. See 5.3.
COMBUSTION AND VENTILATION AIR (DIRECT/NON-DIRECT VENT MODELS) 4. When ducts are used, they shall be of the same crosssectional area as the free area of the openings to which they connect. The minimum dimension of rectangular air ducts shall not be less than 3 inches. 5.3.4 Specially Engineered Installations: The requirements of 5.3.
COMBUSTION AND VENTILATION AIR (DIRECT/NON-DIRECT VENT MODELS) All 90° elbows must be medium radius (1/4 bend DWV) or long radius (Long sweep 1/4 bend DWV) types conforming to ASTM D3311. A medium radius (1/4 bend DWV) elbow measures 3 1/16” minimum from the plane of one opening to the centerline of the other opening for 2” diameter pipe, and 4 9/16” minimum for 3” pipe.
COMBUSTION AND VENTILATION AIR (DIRECT/NON-DIRECT VENT MODELS) • Less than 36 inches from any building opening or any gas service regulator. For gas service regulators in the Province of Ontario, 72 inches. • Less than 72 inches from the combustion air intake of another appliance. • Directly above a gas utility meter or service regulator. • Over a walkway unless located 84 inches above grade.
COMBUSTION AND VENTILATION AIR (DIRECT/NON-DIRECT VENT MODELS) 2. Upflow and Counterflow units. Loosen the worm gear hose clamps on the rubber elbow and detach it from both the induced draft blower and the vent/flue pipe. 3. Upflow and Counterflow units. Remove the vent/flue pipe from the furnace. 4. Cut the vent/ flue pipe at the elbow nearest the coupling end of the pipe (See “ Vent/Flue Pipe Cuts” figure).
COMBUSTION AND VENTILATION AIR (DIRECT/NON-DIRECT VENT MODELS) Alternate Combustion Air Intake Location The alternate combustion air intake location is the large hole not in line with the induced draft blower outlet. To use the alternate combustion air intake location, refer to the following steps, and the “Alternate Combustion Air Intake Location” figure. Note: Counterflow unit instructions follow the upflow instructions. 6. Upflow and Counterflow units.
COMBUSTION AND VENTILATION AIR (DIRECT/NON-DIRECT VENT MODELS) bustion air intake to prevent inadvertent blockage. The tee used in the vent/flue termination must be included when determining the number of elbows in the piping system. Non-Direct Vent (Single Pipe) Maximum Allowable Length of Vent/Flue Pipe (ft) (1) (2) Unit Input (BTU) 45,000 70,000 90,000 115,000 [0 - 4,500 ft] 115,000 [4,500 - 11,000 ft] Pipe (3) Number of Elbows Size (inc.
COMBUSTION AND VENTILATION AIR (DIRECT/NON-DIRECT VENT MODELS) Direct Vent (Dual Pipe) Piping Direct vent installations require both a combustion air intake and a vent/flue pipe. The pipes may be run horizontally and exit through the side of the building or run vertically and exit through the roof of the building. The pipes may be run through an existing unused chimney; however, they must extend a minimum of 12 inches above the top of the chimney.
COMBUSTION AND VENTILATION AIR (DIRECT/NON-DIRECT VENT MODELS) Concentric Vent Termination 12' MIN. 3" MIN. 24" MAX. VENT/FLUE TEE SUPPORT STRAPS COMBUSTION AIR INTAKE. 90° SCREEN MEDIUM RADIUS ELBOWS 12' MIN. ABOVE HIGHEST ANTICIPATED SNOW LEVEL 12' MIN. ABOVE HIGHEST ANTICIPATED SNOW LEVEL The Concentric Vent Kits HCVK and VCVK are designed to allow the terminations of a direct vent furnace to be "concentrically" vented through a wall (HCVK) or roof (VCVK).
CONDENSATE DRAIN LINES AND DRAIN TRAP Condensate Drain Lines and Drain Trap General A condensing gas furnace achieves its high level of efficiency by extracting almost all of the heat from the products of combustion and cooling them to the point where condensation takes place. The condensate which is generated must be piped to an appropriate drain location. In upright installations, the furnace’s drain hoses may exit either the right or left side of the furnace.
CONDENSATE DRAIN LINES AND DRAIN TRAP RIGHT SIDE PANEL Cabinet Width (inches) RUBBER ELBOW RUBBER ELBOW DRAIN PORT TUBE 1 16.5 20.5 HOSE B 24.5 SIDE PANEL GROMMET HOLES TUBE(S) 2 HOSE A Model GUCA & GCCA (kBTU Tons) 045__30 070__30 070__40 090__40 090__50 115__50 "X" Length to Cut From Long End of Hose B (inches) 8 inches 4 inches None 6. Insert short end of each Tube 2 through side panel grommet holes. Secure tubes to Hose A and Hose B with hose clamps.
CONDENSATE DRAIN LINES AND DRAIN TRAP 6. Cut 17 7/8 inches from the long end of Hose B and discard. 7. Secure remaining end of Hose B to exposed end of Tube 1 with a hose clamp. Route hose toward right side panel grommet holes. 8. Insert short end of one Tube 2 through rear right side panel grommet drain hole. Secure tube to Hose A with hose clamp. 9. Insert short end of remaining Tube 2 into Hose B from rubber elbow and secure with hose clamp.
CONDENSATE DRAIN LINES AND DRAIN TRAP 2. Upflow furnaces Relocate the front cover pressure switch hose connection from the right side (as shipped) pressure tap to the left (down) side tap. The pressure switch hose must be connected to the down side to guard against blocked drain conditions. Cut hose to appropriate length to minimize sagging. Plug right (unused) pressure tap with plug removed from left side. 3. Secure Hose A to front cover drain port with a hose clamp.
PRODUCT DESIGN Safety Please adhere to the following warnings and cautions when installing, adjusting, altering, servicing, or operating the furnace. WARNING To prevent personal injury or death due to improper installation, adjustment, alteration, service or maintenance, refer to this manual. For additional assistance or information, consult a qualified installer, service agency or the gas supplier.
PRODUCT DESIGN and Combustion Air Pipe -Termination Locations section to determine if the piping system from furnace to termination can be accomplished within the guidelines given. Note: The length of flue and/or combustion air piping can be a limiting factor in the location of the furnace. A copy of the National Fuel Gas Code (NFPA 54/ANSI Z223.
PRODUCT DESIGN closed non-direct vent furnace has an adequate supply of combustion air, vent from a nearby uncontaminated room or from outdoors. Refer to the Combustion and Ventilation Air Requirements section for details. • If the furnace is used in connection with a cooling unit, install the furnace upstream or in parallel with the cooling unit. Premature heat exchanger failure will result if the cooling unit is placed ahead of the furnace.
PRODUCT DESIGN Existing Furnace Removal Note: When an existing furnace is removed from a venting system serving other appliances, the venting system may be too large to properly vent the remaining attached appliances. • Drafts, or dead spots behind doors, in corners, or The following vent testing procedure is reproduced from the American National Standard/National Standard of Canada for Gas-Fired Central Furnaces ANSI Z21.471993, CAN/CGA-2.3-M93 Section 1.23.1. • Light fixtures or other appliances.
PRODUCT DESIGN Alternate Vent/Flue and Combustion Air Connections In horizontal installations provisions for alternate flue and combustion air piping are available for upflow furnaces with left discharge and counterflow furnaces with right air discharge. In these positions the flue and combustion air piping can be run vertically through the side of the furnace. Refer to the “Recommended Installation Positions” figure for further detail. The standard piping connections may also be used in these positions.
PRODUCT DESIGN Use a separate fused branch electrical circuit containing properly sized wire, and fuse or circuit breaker. The fuse or circuit breaker must be sized in accordance with the maximum overcurrent protection specified on the unit rating plate. An electrical disconnect must be provided at the furnace location. 4. Verify that wires will not interfere with circulator blower operation, filter removal, or routine maintenance. 5. Reinstall blower compartment door. 6.
PRODUCT DESIGN 115 Volt Line Connection of Accessories (Humidifier and Electronic Air Cleaner) WARNING To avoid electrical shock, injury or death, disconnect electrical power before servicing, or changing any electrical wiring. The furnace’s integrated control module is equipped with line voltage accessory terminals for controlling power to an optional field-supplied humidifier and/or electronic air cleaner. Accessory Load Specifications Humidifier 1.0 Amp maximum at 120 VAC Electronic Air Cleaner 1.
PRODUCT DESIGN MANUAL SHUT OFF VALVE (UPSTREAM FROM GROUND JOINT PIPE UNION) GAS VALVE MANUAL SHUT OFF VALVE (UPSTREAM FROM GROUND JOINT PIPE UNION) HEIGHT REQUIRED BY LOCAL CODE * * GROMMET IN STANDARD GAS LINE HOLE * * * GROUND JOINT PIPE UNION * * PLUG IN ALTERNATE GAS LINE HOLE HEIGHT REQUIRED BY LOCAL CODE * PLUG IN ALTERNATE GAS LINE HOLE * ALTERNATE GAS LINE LOCATION ALTERNATE GAS LINE LOCATION * BURNERS * MANIFOLD GAS VALVE GROMMET IN STANDARD GAS LINE HOLE MANIFOLD DRIP LEG
PRODUCT DESIGN A different pressure switch may be required at high altitude regardless of the BTU/ft3 content of the fuel used. Refer to S-19 HIGH ALTITUDE APPLICATION (USA) section located in the SERVICING section of this manual or an Amana distributor for a tabular listing of appropriate altitude ranges and corresponding manufacturer’s pressure switch kits. Propane Gas Conversion WARNING Possible death, personal injury or property damage may occur if the correct conversion kits are not installed.
PRODUCT DESIGN • Use listed gas appliance connectors in accordance with their instructions. Connectors must be fully in the same room as the furnace Note: Never exceed specified pressures for testing. Higher pressure may damage the gas valve and cause subsequent overfiring, resulting in heat exchanger failure. • Protect connectors and semirigid tubing against physical and thermal damage when installed.
PRODUCT DESIGN Refer to the following illustration for typical propane gas installations. A duct system must be installed in accordance with Standards of the National Board of Fire Underwriters for the Installation of Air Conditioning, Warm Air Heating and Ventilating Systems. Pamphlets No. 90A and 90B. A closed return duct system must be used, with the return duct connected to the furnace. Supply and return connections to the furnace may be made with flexible joints to reduce noise transmission.
PRODUCT DESIGN To ensure proper unit performance follow the filter sizes given in the following filter sizing charts.
PRODUCT DESIGN Heat Anticipator Setting The heat anticipator in the room thermostat must be correctly adjusted to obtain the proper number of cycles per hour and to prevent “overshooting” of the setting. Set the heat anticipator setting to 0.7 amps. Follow the thermostat manufacturer’s instructions on how to adjust the heat anticipator setting and refer to S-3B Heating Anticipator section in the SERVICING section of this manual. Drain Trap Priming The drain trap must be primed prior to furnace startup.
PRODUCT DESIGN 120 2 1 90 2 1 ON OFF 120 2 1 OFF ON 90 120 180 90 OFF OFF 120 180 60 180 Second Delay ON ON 180 2 1 120 Second Delay 180 60 46 Rev. 0 90 Second Delay Jumper 60 Blower Heat Off Delay Timings The integrated control module provides a selectable heat off delay function. The heat off delay period may be set to 60, 90, 120, 180 seconds using the DIP switches or jumper provided on the control module.
SYSTEM OPERATION Normal Sequence of Operation Power Up The normal power up sequence is as follows: • 115 VAC power applied to furnace. • Integrated control module performs internal checks. • Integrated control module flashes LED one time. • Integrated control module monitors safety circuits continuously. • Furnace awaits call from thermostat. Heating Mode The normal operational sequence in heating mode is as follows: • R and W thermostat contacts close, initiating a call for heat.
SYSTEM OPERATION TIMING CHART FOR NORMAL HEATING OPERATION CIRCULATOR BLOWER ON OFF GAS VALVE OPEN CLOSED IGNITER ON OFF PRESSURE SWITCH CONTACTS OPEN CLOSED INDUCED DRAFT BLOWER ON OFF THERMOSTAT ON OFF SECONDS t ign 0 IGNITER WARM UP PERIOD (see note) t circ 0 15 FIXED HEAT ON DELAY: 30 SECONDS NOTE: HEATCRAFT INTEGRATED CONTROL MODULE HAS A FIXED STANDARD SEVEN-SECOND IGNITER WARM UP PERIOD (MINI IGNITER).
SYSTEM OPERATION Troubleshooting Electrostatic Discharge (ESD) Precautions Note: Discharge body’s static electricity before touching unit. An electrostatic discharge can adversely affect electrical components. Use the following precautions during furnace installation and servicing to protect the integrated control module from damage.
Rev. 0 TROUBLESHOOTING CHART Symptoms of Abnormal Operation - Furnace fails to operate. and - Integrated control module diagnostic LED provides no signal. - Furnace fails to operate. and - Integrated control module diagnostic LED is lit continuously. - Furnace fails to operate. and - Integrated control module diagnostic LED is flashing two flashes. - Induced draft blower runs continuously with no further furnace operation. and - Integrated control module diagnostic LED is flashing three flashes.
TROUBLESHOOTING CHART Symptoms of Abnormal Operation Associated LED Code (See Note 2) Fault Description(s) Possible Causes Corrective Action Cautions and Notes - Turn power OFF prior to repair. 7 - Normal furnace operation. but - Integrated control module diagnostic LED is flashing seven flashes. - Flame sensor is coated/oxidized. 7 Flashes White Rodgers Control Only - Flame sense micro-amp signal is low. - Sand flame sensor if coated/oxidized. Inspect for proper sensor alignment.
POLARIZATION AND PHASING As more and more electronic's are introduced to the Heating Trade, Polarization of incoming power and phasing of primary to secondary voltage on transformers becomes more important. Incoming Power Meter Reads Meter Reads 120 Volts 0 Volts Polarization has been apparent in the Appliance industry since the introduction of the three prong plug, however, the Heating Industry does not use a plug for incoming power, but is hard wired.
MAINTENANCE WARNING TO AVOID ELECTRICAL SHOCK, INJURY OR DEATH, DISCONNECT ELECTRICAL POWER BEFORE PERFORMING ANY MAINTENANCE. CAUTION IF YOU MUST HANDLE THE IGNITOR, HANDLE WITH CARE. TOUCHING THE IGNITOR BODY WITH BARE FINGERS, ROUGH HANDLING, OR VIBRATION COULD RESULT IN EARLY IGNITOR FAILURE. ONLY A QUALIFIED SERVICER SHOULD EVER HANDLE THE IGNITOR. Remember that dirty filters are the most common cause of inadequate heating or cooling performance.
MAINTENANCE 3. Remove filters 9. Clean residue from furnace using a vacuum cleaner. 4. Remove blower compartment door. Vacuum compartment. Replace blower compartment door. 10. Replace the parts removed in the previous steps in reverse order. 5. Replace filters opposite of removal. 6. Replace access door in ductwork. 11. Turn on electrical power and gas to furnace. Check for leaks and proper unit operation.
SERVICING TEST EQUIPMENT Proper test equipment for accurate diagnosis is as essential as regulator hand tools. The following is a must for every service technician and service shop. Multiplying the ninety (90) cubic feet by 1025 BTU gives us an input of 92,250 BTUH. Checking the BTU input on the rating plate of the furnace being tested. EXAMPLE: GUCA090AX40 1. Dial type thermometers or thermocouple meter (optional) - to measure dry bulb temperature. INPUT: 92,000 BTU/HR 2.
SERVICING 1 0 9 8 3 7 7 4 5 6 1 Million Quarter Foot 1 1 9 2 2 8 0 8 3 3 6 5 4 8 2 3 7 7 4 100 Thousand 1 9 9 2 5 6 10 Thousand 6 5 4 1 Thousand CUBIC FEET One Foot GAS RATE - CUBIC FEET PER HOUR GAS RATE -- CUBIC FEET PER HOUR Seconds for One Revolution 1/4 cu/ft 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 90 82 75 69 64 60 56 53 50 47 45 43 41 39 37 36 34 33 32 31 30 -28 -26 -- 56 Rev.
SERVICING Power Failure Blown Fuse Loose Connection Shorted or Broken Wires No Low Voltage Faulty Thermostat Faulty Transformer Poor or High Resistance Ground Improper Heat Anticipator Setting Improper Thermostat Location Faulty Limit or Roll Out Switch Faulty Flame Sensor Faulty Ignition Control Gas Valve or Gas Supply Shut Off Faulty Induced Draft Blower Broken or Shorted Igniter Dirty Flame Sensor, Low uA Flame Sensor not in Flame, Low uA Faulty Gas Valve Open Auxiliary Limit Improper Air Flow or Distri
SERVICING SECTION INDEX 58 Rev.
SERVICING Disconnect Electrical Power Supply: S-3 CHECKING THERMOSTAT, WIRING, AND ANTICIPATOR 1. Remove blower compartment door from furnace to gain entry to Junction Box. S-3A Thermostat and Wiring S-1 CHECKING VOLTAGE 2. Remove cover from Junction Box to gain access to incoming power lines. With Power ON: WARNING Disconnect Electrical Power Supply: LINE VOLTAGE NOW PRESENT. 1.
SERVICING GUCA / GCCA Ignition Control Heat Anticipator Setting White-Rodgers 50A55-288 .70 amps Heatcraft HSI-2 .70 amps If the anticipator current draw is unknown, then an amp draw should be taken to determine the anticipator setting. Use an amprobe as shown below. Wrap 10 turns of thermostat wire around the stationary jaw of the amprobe and divide the reading by 10.
SERVICING 4. After completing check and/or replacement of primary limit control, reinstall burner compartment door. 5. Turn on electrical power and verify proper unit operation VOLT / OHM METER To aid in identifying these controls, these controls have a color coded marking on them. Refer to the following chart for temperature settings and color codes. T.O.D.
SERVICING If the windings do not test continuous or a reading is obtained from lead to ground, replace the motor. a. Good Condition - indicator swings to zero and slowly returns toward infinity. 5. After completing check and/or replacement of blower motor, reinstall blower compartment door. b. Shorted - indicator swings to zero and stops there - replace. 6. Turn on electrical power and verify proper unit operation. c. Open - no reading - replace. Reverse leads. Check again no reading - replace. d.
SERVICING 2. Next, remove wire connections from gas valve terminals. 3. Using an ohmmeter, test across the gas valve coil terminals M1 and C2. Note: Make sure gas valve switch is in the "ON" position when taking reading. 4. Should read approximately 100 Ohms for the WhiteRodgers 36E22 gas valve. If not as above, replace the entire gas valve. 5. After check and/or replacement of gas valve, turn on gas to furnace and check for leaks. If leaks are found, repair and then reinstall burner compartment door. 6.
SERVICING 6. After check and/or replacement of orifice(s) reinstall manifold to burner bracket. 7. Turn on gas to furnace and check for leaks. If leaks are found, repair and then reinstall burner compartment door. Gas Line Gas Shutoff Valve 8. Turn on electrical power and verify proper unit operation.
SERVICING Gas Manifold Pressure Measurement and Adjustment CAUTION 6. Turn the adjustment screw clockwise to increase the pressure, or counterclockwise to decrease the pressure. 7. Securely replace the regulator cap. To prevent unreliable operation or equipment damage, the gas manifold pressure must be as specified on the unit rating plate. Only minor adjustments should be made by adjusting the gas valve pressure regulator.
SERVICING S-15 CHECKING DUCT STATIC S-16 CHECKING TEMPERATURE RISE The maximum and minimum allowable external static pressures are found in the specification section. These tables also show the amount of air being delivered at a given static by a given motor speed or pulley adjustment. The more air (CFM) being delivered through a given furnace, the less the rise will be; so the less air (CFM) being delivered, the greater the rise.
SERVICING PRESSURE SWITCH TRIP POINTS AND USAGE CHART PRESSURE SWITCH TRIP POINTS AND USAGE NEGATIVE PRESSURE 0 to 7,000 ft. 7,001 to 11,000 ft.
SERVICING S-17 CHECKING PRESSURE CONTROL A pressure control device is used to measure negative pressure at the induced draft blower motor inlet to detect a partial or blocked flue and also a pressure control device is used to measure negative pressure at the recuperator coil cover to detect a partial or blocked recuperator coil or drain. 5.
SERVICING The following chart give the orifice drill size and high altitude kit required for different elevations. High altitude pressure switches and kits are listed on the page 67 in the Pressure Switch Usage and Trip Point Chart. Note: In Canada, gas furnaces are certified only to 4500 feet. ORIFICE SIZE AND HIGH ALTITUDE KIT CHART GUCA GCCA 0 to 7,000 ft. GUCA GCCA 7,001 to 9,000 ft. Nat. #44 GUCA GCCA 7,001 to 11,000 ft. Nat. #45 GUCA GCCA 0 to 7,000 ft.
SERVICING The indicator light may then be viewed by looking through the peep hole in the blower access door. Failure to hold the door switch closed while removing the blower compartment door will result in the loss of the stored failure code. In most cases recycling the ignition control will result in the same failure code originally displayed. 1. Remove the blower compartment door to gain access to the control area. 2.
SERVICING ing) is established, the hot surface ignitor will be deenergized. 6. The micro-amp reading should be 1 to 4 micro-amps. If the micro-amp reading is less than the minimum specified, check for high resistance wiring connections, coated flame sensor, the distance between the sensor and flame ground connections or poor grounding. Note: Contaminated fuel or combustion air can create a nearly invisible coating on the flame sensor.
SERVICING a. If no voltage is measured on either side of control it indicates that either the ignition control or wiring to control is the problem. Removal of Existing Heat Exchanger: b. If voltage is measured on one side of the control and not the other it indicates the control is open. Disconnect Electrical Power and Shut Off Gas Supply: WARNING c. If voltage is measured on both sides of the control the wiring to gas valve or valve is at fault.
SERVICING Reinstallation of New Heat Exchanger: Note: Before installing new heat exchanger assembly, inspect gasket along inside rails. If the gasket needs replacing, install the new pieces of gasket supplied with kit. 1. Slide new heat exchanger into cabinet and secure with screws removed in Step 8 of removal procedures. Reinstall the permagum in the top and bottom corners between the heat exchanger and cabinet, that is used to help seal the burner compartment area. 2.
Rev.
RD -2 WH -33 HOT SURFACE IGNITER 2 PIN CONNECTOR C2 P3 M1 BR-13 GY-34 C NO GND FLAME SENSOR GN GY-12 FRONT C OVER PRESSU RE SWITCH VT -28 WH 33 RD-11 OR-15 GY-12 RD-11 BU-14 BR-13 WH -5 BK -4 BK -1 L OL AT HEAT-H HE CO COOL-H GND ELECTRONIC AIR CLEANER INDOOR AIR CIRCULATION BLWR ID BLWR HUMIDIF IER HOT SURFACE IGNITER N C C LINE-N EAC-N CIR-N GAS VALVE ID BLOWER PRESSU RE SWITCH NO AUTO RESET PRIMARY LIMIT CONTROL XFMR-N HUM-N GND C2 P3 M1 MANUAL RESET AUXILIAR
Rev. 0 TYPICAL SCHEMATIC GUCA MODEL FURNACES 10207709 WR50A55 INTEGRATED IGNITION CONTROL This schematic is for reference only. Not all wiring is as shown above, refer to the appropriate wiring diagram for the unit being serviced. ! WARNING FLAME SENSOR PROBE IGN IGNITOR FP 3M .
TYPICAL SCHEMATIC GCCA MODEL FURNACES 11184504 HSI-2 INTEGRATED IGNITION CONTROL This schematic is for reference only. Not all wiring is as shown above, refer to the appropriate wiring diagram for the unit being serviced. ! WARNING FLAME SENSOR PROBE IGN IGNITER FP GND GAS VALVE MVC MV CIR PARK PARK NEU EAC ELECTRONIC AIR CLEANER PS HLO PRESSURE SWITCH IND INDUCER HIGH LIMIT EAU NEU TO AVOID POSSIBLE ELECTRICAL SHOCK, PERSONAL INJURY, OR DEATH, DISCONNECT THE POWER BEFORE SERVICING.
FURNACE TWINING KIT - FTK03A This schematic is for reference only. Not all wiring is as shown above, refer to the appropriate wiring diagram for the unit being serviced. 78 Rev. 0 ! WARNING * Tape wire ends if not used. TO AVOID POSSIBLE ELECTRICAL SHOCK, PERSONAL INJURY, OR DEATH, DISCONNECT THE POWER BEFORE SERVICING.
