Service Instructions Goodman® Brand GMEC96 & Amana® Brand AMEC96 Two Stage Furnace with multi-speed ECM Motor 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. The material in this manual does not supercede manufacturers installation and operation instructions.
TABLE OF CONTENTS IMPORTANT INFORMATION ............................... 3 SYSTEM OPERATION. ..................................... 26 PRODUCT IDENTIFICATION .............................. 5 ACCESSORIES ................................................. 38 FURNACE SPECIFICATIONS...............................7 SERVICING TABLE OF CONTENTS..................42 OPERATING INSTRUCTIONS..............................8 SERVICING ........................................................
IMPORTANT INFORMATION RISQUE D'EMPOISONNEMENT AU MONOXYDE DE CARBONE Advertencia especial para la instalación de calentadores ó manejadoras de aire en áreas cerradas como estacionamientos ó cuartos de servicio. Las emisiones de monóxido de carbono pueden circular a través del aparato cuando se opera en cualquier modo. CO can cause serious illness including permanent brain damage or death.
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PRODUCT IDENTIFICATION The model and manufacturing number are used for positive identification of component parts used in manufacturing. Please use these numbers when requesting service or parts information.
PRODUCT IDENTIFICATION MODEL # MFG # DESCRIPTION AFE18-60A N/A Fossil Fuel Kit. The AFE18-60A control is designed for use where the indoor coil is located above/downstream of a gas or fossil fuel furnace when used with a heat pump. It will operate with single and two stage heat pumps and single and two stage furnaces AMU1620 AMU1625 AMU2020 AMU2025 GMU1620 GMU1625 GMU2020 GMU2025 6 P1251305F P1251306F P1251307F P1251308F Media Air Cleaner.
FURNACE SPECIFICATIONS Heating Data Hi gh Fire Input¹ Hi gh Fire Output¹ Low-Fire Stea dy-Sta te Input¹ Low-Fire Stea dy-Sta te Output¹ AFUE² Temperature Ri s e Ra nge (°F) Vent Dia meter³ No. of Burners Circulator Blower Avai la ble AC @ 0.5” ESP Si ze (D x W) Hors epower @ 1075 RPM Speed Electrical Data 4 Min. Circui t Ampa city Ma x.
OPERATIONS INSTRUCTIONS Introduction This is a Category lV furnace. This furnace uses a pressurized venting system and must be installed per National and local codes requirements and the installation manual that was shipped with the furnace. The *MEC96 34.5" furnace is one of the products in our newly redesigned line of shorter chassis furnaces. It is available in the following sizes and suitable for up flow / horizontal installation.
INSTALLATION CONSIDERATIONS • WARNING TO PREVENT PROPERTY DAMAGE, PERSONAL INJURY OR DEATH DUE TO FIRE, DO NOT INSTALL THIS FURNACE IN A MOBILE HOME, TRAILER, OR RECREATIONAL VEHICLE. To ensure proper furnace operation, install, operate, maintain and service the furnace in accordance with the installation, operation and service instructions, all local building codes and ordinances. In their absence, follow the latest edition of the National Fuel Gas Code (NFPA 54/ANSI Z223.
INSTALLATION CONSIDERATIONS • • • • carbon tetrachloride halogen type refrigerants cleaning solutions (such as perchloroethylene) printing inks paint removers varnishes hydrochloric acid cements and glues antistatic fabric softeners for clothes dryers and masonry acid washing materials Isolate a non-direct vent furnace if it is installed near an area frequently contaminated by any of the above substances. This protects the non-direct vent furnace from airborne contaminants.
INSTALLATION CONSIDERATIONS PROVIDE 8" MINIMUM CLEARANCE BETWEEN CENTER ROD AND FURNACE CABINET TO ALLOW FOR CIRCULATOR BLOWER REMOVAL. 3/8" DIAMETER ALTERNATE THREADED ROD GAS PIPING ASSURE FURNACE IS LEVEL FROM END TO END. ON 90% FURNACES MAKE SURE (6 PLACES) THE UNIT HAS A SLIGHT FORWARD TILT WITH THE FRONT OF THE FURNACE 0"-3/4" HOLD DOWN BELOW THE BACK OF THE FURNACE.
INSTALLATION CONSIDERATIONS Most homes will require outside air be supplied to the furnace area by means of ventilation grilles or ducts connecting directly to the outdoors or spaces open to the outdoors such as attics or crawl spaces. The following information on air for combustion and ventilation is reproduced from the National Fuel Gas Code NFPA 54/ANSI Z223.1 Section 9.3. 9.3* Air for Combustion and Ventilation.
INSTALLATION CONSIDERATIONS Chimney or Gas Vent Ventilation louvers (each end of attic) NOTE: The inlet and outlet air openings must each have a free area of not less than one square inch per 4000 BTU of the total input rating of all equipment in the enclosure. Outlet Air Water Heater Furnace Inlet Air Alternate air inlet 9.3.3.2* One Permanent Opening Method. One permanent openings, commencing within 12 in. (300 mm) of the top of the enclosure, shall be provided.
INSTALLATION CONSIDERATIONS 9.3.6.2 Each of the appliances served shall be interlocked to the mechanical air supply system to prevent main burner operation where the mechanical air supply system is not in operation. 9.3.6.3 Where combustion air is provided by the building’s mechanical ventilation system, the system shall provide the specified combustion air rate in addition to the required ventilation air. 9.3.7 Louvers, Grilles, and Screens. 9.3.7.1 Louvers and Grilles.
INSTALLATION CONSIDERATIONS have a slight tilt with the access doors downhill (approximately 3/4") from the back panel. The slight tilt allows the heat exchanger condensate, generated in the recuperator coil, to flow forward to the recuperator coil front cover. AIR DISCHARGE Side Return Duct Connection Side Return Duct Connection Bottom Return Duct Connection UPFLOW UPRIGHT 1. Remove screws from the vent flange. 2. Remove the internal elbow and vent pipe 3. Cut 2 1/2" from the flange . 4.
INSTALLATION CONSIDERATIONS Propane Gas and/or High Altitude Installations WARNING POSSIBLE PROPERTY DAMAGE, PERSONAL INJURY OR DEATH MAY OCCUR IF THE APPROPRIATE KITS MUST BE APPLIED TO INSURE SAFE AND PROPER FURNACE OPERATION. ALL ensure that all piping and connections possess adequate structural integrity and support to prevent flue pipe separation, shifting, or sagging during furnace operation. Materials and Joining Methods THE CORRECT CONVERSION KITS ARE NOT INSTALLED.
INSTALLATION CONSIDERATIONS NOTE: In Canada, the B149 Fuel Gas Code takes precedence over the preceding termination restrictions. *MEC96 Direct Vent (2 - Pipe) and Non-Direct Vent (1- Pipe) (6 ) Maximum Allow able Lengt h of Vent/ Flue Pipe Pipe Size Unit Input (Bt u) OTHER THAN COMBUSTION AIR TERMINATION INTAKE (4 ) (in.
INSTALLATION CONSIDERATIONS 10”- 24” TEE (OPTIONAL) 6” MAX COMBUSTION AIR INTAKE (OPTIONAL) 12” MIN HEIGHT DIFFERENCE BETWEEN INTAKE AND VENT *Not required for single pipe installation L OF RO INE 4” MIN 90º OR 45° ELBOW X. MA ” 96 IN. ”M 3 12" MIN. TO GRADE OR HIGHEST ANTICIPATED SNOW LEVEL 12” MIN TO ROOF OR HIGHEST ANTICIPATED SNOW LEVEL Standard Horizontal Terminations (Dual Pipe) ELBOWS 90° ELBOWS STRAIGHT 12" MIN.
INSTALLATION CONSIDERATIONS VENT/INTAKE TERMINATIONS FOR INSTALLATION OF MULTIPLE DIRECT VENT FURNACES If more than one direct vent furnace is to be installed vertically through a common roof top, maintain the same minimum clearances between the exhaust vent and air intake terminations of adjacent units as with the exhaust vent and air intake terminations of a single unit.
INSTALLATION CONSIDERATIONS Vent Combustion Air Maintain 12" (18" for Canada) minimum clearance above highest anticipated snow level. Maximum of 24" above roof. WITH ALL OTHER HOUSEHOLD GAS FIRED APPLIANCES OPERATING. Support (Field Supplied) 45 Elbow (Field Supplied) 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.
INSTALLATION CONSIDERATIONS PROPANE GAS CONVERSION WARNING POSSIBLE PROPERTY DAMAGE, PERSONAL INJURY OR DEATH MAY OCCUR IF THE CORRECT CONVERSION KITS ARE NOT INSTALLED. THE APPROPRIATE KITS MUST BE APPLIED TO INSURE SAFE AND PROPER FURNACE OPERATION. ALL CONVERSIONS MUST BE PERFORMED BY A QUALIFIED INSTALLER OR SERVICE AGENCY. This unit is configured for natural gas. The appropriate manufacturer’s propane gas conversion kit, must be applied for propane gas installations.
INSTALLATION CONSIDERATIONS GAS PIPING CHECKS Before placing unit in operation, leak test the unit and gas connections. WARNING TO AVOID THE Complete information regarding tank sizing for vaporization, recommended regulator settings, and pipe sizing is available from most regulator manufacturers and propane gas suppliers. Refer to the following illustration for typical propane gas installations and piping. POSSIBLITY OF EXPLOSION OR FIRE, NEVER USE A MATCH OR OPEN FLAME TO TEST FOR LEAKS.
INSTALLATION CONSIDERATIONS WARNING IF THE INFORMATION IN THESE INSTRUCTIONS IS NOT FOLLOWED EXACTLY, A FIRE OR EXPLOSION MAY RESULT CAUSING PROPERTY DAMAGE, PERSONAL INJURY OR LOSS OF LIFE. – DO NOT STORE OR USE GASOLINE OR OTHER FLAMMABLE VAPORS AND LIQUIDS IN THE VICINITY OF THIS OR ANY OTHER APPLIANCE. – WHAT TO DO IF YOU SMELL GAS: • DO NOT TRY TO LIGHT ANY APPLIANCE. • DO NOT TOUCH ANY ELECTRICAL SWITCH; DO NOT USE ANY PHONE IN YOUR BUILDING.
INSTALLATION CONSIDERATIONS 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. NOTE: Line polarity must be observed when making field connections.
INSTALLATION CONSIDERATIONS Y2 W1 W2 Y W1 W2 Fur nace Int egrat ed Cont r ol Module Room Thermostat Furnace 1 Furnace 2 Y2 Ylo Ylo Y Y Y W W W W2 W2 W2 R R R G G G C C C Y2 Remot e Condensing Unit (Tw o-St age Cooli ng) Thermostat - Two-Stage Heating with Two-Stage Cooling Thermostat Wiring Diagrams SINGLE-STAGE HEATING THERMOSTAT APPLICATION A single-stage thermostat with only one heating stage may be used to control this furnace.
SYSTEM OPERATION *The blower speed wiring connections must remain in factory position. 1. Refer to the air flow table for your specific model furnace. 2. If a cooling or heat pump condensing unit is being used in conjunction with this furnace, the three DIP switches in S2 are used to select the proper cooling speeds to match the outdoor unit size. Typical CFM requirements are 400 CFM / Ton. 1. Turn OFF power to the furnace. 2.
SYSTEM OPERATION DIP SWITCH SETTINGS COOLING *MEC960302BN DIP SWITCH SETTING St at i c 0. 1 0. 2 0. 3 0. 4 0. 5 0. 6 0. 7 0.
SYSTEM OPERATION DIP SWITCH SETTINGS COOLING DIP SWITCH SETTING *MEC960402BN Static Switch Bank 2 G Switch 1 2 3 Ylo **OFF OFF OFF Y Ylo Y ON OFF OFF Ylo Y ON ON OFF Ylo Y OFF OFF ON Ylo Y OFF ON ON Ylo Y ON OFF ON 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.
SYSTEM OPERATION DIP SWITCH SETTINGS *MEC960603BN COOLING DIP SWITCH SETTING Static Switch Bank 2 G Switch 1 2 3 Ylo Y **OFF OFF OFF Ylo Y ON OFF OFF Ylo Y ON ON OFF Ylo Y OFF OFF ON Ylo Y OFF ON ON 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.
SYSTEM OPERATION DIP SWITCH SETTINGS COOLING DIP SWITCH SETTING *MEC960803BN Static Switch Bank 2 G Switch 1 2 3 Ylo **OFF OFF OFF Y Ylo Y ON OFF OFF Ylo Y ON ON OFF Ylo Y OFF ON OFF Ylo Y OFF OFF ON Ylo Y OFF ON ON 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.
SYSTEM OPERATION DIP SWITCH SETTINGS *MEC960804CN COOLING DIP SWITCH SETTING Switch Bank 2 G Switch 1 2 3 Ylo **OFF OFF OFF Y Ylo Y ON ON OFF Ylo Y OFF ON OFF Ylo Y OFF OFF ON Ylo Y OFF ON ON 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.
SYSTEM OPERATION DIP SWITCH SETTINGS *MEC961004CN COOLING DIP SWITCH SETTING Switch Bank 2 G Switch 1 2 3 Ylo **OFF OFF OFF Y Ylo ON OFF OFF Y Ylo Y ON ON OFF Ylo OFF ON OFF Y Ylo OFF OFF ON Y Ylo Y OFF ON ON 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.
SYSTEM OPERATION DIP SWITCH SETTINGS *MEC961005CN COOLING DIP SWITCH SETTING Switch Bank 2 G Switch 1 2 3 Ylo Y **OFF OFF OFF Ylo Y ON ON OFF Ylo Y OFF OFF ON Ylo Y OFF ON ON Ylo Y ON OFF ON 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.
SYSTEM OPERATION DIP SWITCH SETTINGS *MEC961205DN COOLING DIP SWITCH SETTING Switch Bank 2 G Switch 1 2 3 Ylo Y **OFF OFF OFF Ylo Y ON OFF OFF Ylo Y ON ON OFF Ylo Y OFF ON OFF Ylo Y OFF OFF ON Ylo Y OFF ON ON 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.
SYSTEM OPERATION Refer to Minimum Filter Area tables to determine filter area requirement. NOTE: Filters can also be installed elsewhere in the duct system such as a central return. Horizontal Installations Filter(s) must be installed external to the furnace casing for horizontal installations. For most installations it is preferable to use a central return with filters installed in the duct behind the return air grill.
SYSTEM OPERATION 2ND STAGE SATISFIED, FIRST STAGE STILL CALLED: · · When the second stage of the thermostat is satisfied, the inducer blower is reduced to low speed which deenergizes the second stage of the gas valve. After the high heat off delay expires, the circulator is reduced to low heat speed.
SYSTEM OPERATION SINGLE COOLING STAGE THERMOSTAT OR 2ND STAGE COOLING MODE SEQUENCE. · · · · · · On a call for cool, the Y and G thermostat contacts close signaling the control module. The LED will display a “GREEN”2 flash The compressor and condenser fan are energized. The compressor is connected to the Y terminal of the control module. The circulator fan is energized at cool speed after a cool on delay. The electronic air cleaner will also be energized.
EFR02 AFE18-60A AMU / GMU ASAS / GSAS 0170K00000S 0170K00001S DCVK-20 (CVENT-2) DCVK-30 (CVENT-3) LPM30 LPM08 LPLP03 RF000142 EFR External Filter Rack Dual Fuel Kit Media Air Cleaners Electronic Air Cleaner Concentric Side Wall Flush Mount Vent Kit (3") Concentric Side Wall Flush Mount Vent Kit (2") Concentric Vent Kit (2") Concentric Vent Kit (3") Propane Gas Conversion Kit Propane Gas Conversion Kit LP Low Pressure Shut Off Kit Vent Drain Coupling HASFK-1 HASFK-2 HASFK-3 HASFK-1 HASFK-2
ACCESSORIES EXTERNAL FILTER RACK KIT ( EFR02 ) EFR01 EXTERNAL FILTER RACK KIT SLOTS IN FILTER CLEAR SCREWS ON UNIT Used on Models 90% Upflow Model Furnaces BLOWER DECK SCREWS UNIT SIDE PANEL FRONT OF UNIT FILTER RACK ASSEMBLY (FACE FILTER OPENING TOWARDS FRONT OF UNIT) BASE OF UNIT RETURN AIR CUTOUT AREA LOWER EDGE SCREW SIDE WALL VENT KIT (0170K00000S/0170K00001S) Description This side wall only vent kit #0170K00000S is to be used with 2” - 3” vent systems.
ACCESSORIES CONCENTRIC VENT CONVERSION KIT ( DCVK-20 DCVK-30 ) ( CVENT-2 ) ( CVENT-3 ) Vent The DCVK-20 (2") or the DCVK30 (3") is a concentric vent kit approved with furnaces listed in Combustion Air this manual. This concentric vent kit allows for Roof Boot/Flashing vertical or horizontal vent termination. The illustrations give a brief(Field Supplied) view of the kit and its application.
ACCESSORY WIRING DIAGRAMS HIGH VOLTAGE! DISCONNECT ALL POWER BEFORE SERVICING OR INSTALLING THIS UNIT. MULTIPLE POWER SOURCES MAY BE PRESENT. FAILURE TO DO SO MAY CAUSE PROPERTY DAMAGE, PERSONAL INJURY OR DEATH.
SERVICING SERVICE NUMBERS S-1 CHECKING VOLTAGE ................................................................................................................................. 49 S-2 CHECKING WIRING .................................................................................................................................... 49 S-3A S-3B THERMOSTAT AND WIRING .......................................................................................................................
SERVICING 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.
SERVICING 1 1 CUBIC FEET One GAS RATE -- CUBIC FEET PER HOUR Size of Test Dial 5 cu/ft Seconds for One Revolution 1/4 cu/ft 1/2 cu/ft 1 cu/ft 2 cu/ft 5 cu/ft 720 1800 36 25 50 100 200 500 327 300 655 600 1636 1500 37 38 -23 -47 97 95 195 189 486 474 138 129 277 257 555 514 1385 1286 39 40 -22 -45 92 90 185 180 462 450 60 56 120 113 240 225 480 450 1200 1125 41 42 -21 -43 -86 176 172 439 429 53 106 212 424 1059 -- -- -- 167 419 50 47 100 95 200 18
SERVICING Power Failure Blown Fuse Loose Connection Shorted or Broken Wires No Low Voltage Faulty Thermostat Faulty Transformer Poor or High Resistance Ground • • • • • • • Faulty Ignition Control Gas Valve or Gas Supply Shut Off Faulty Induced Draft Blower Faulty Blower Motor (PSC) Broken or Shorted Ignitor Dirty Flame Sensor, Low UA Stuck Gas Valve Faulty Gas Valve Open Auxiliary Limit Improper Air Flow or Distribution Cycling on Limit Delayed Ignition • • • • • • • • • • • • • • • • • • • • • • •
TROUBLESHOOTING Symptoms Green LED Code Amber LED Code Red LED Code Fault Description Check Cautions •Furnace fails to operate •None •Control board LED is off •None •None •Defective disconnect switch •Determine cause and restore •Confirm electrically safe •defective door switch • No proper high and low volt power condition before 115 volt power •No 24 volt supply proceeding with repairs power •Furnace is waiting for a •Solid ON call •None •None •Furnace is not receiving a call •None Required
TROUBLESHOOTING Symptoms Green LED Code Amber LED Code Red LED Code Fault Description Check Cautions •Temperature rise, duct static, •Confirm electrically safe gas pressure, burner alignment, condition before orifice plate position, wiring to proceeding with repairs all limits •None •Four repeating flashes •Open limit circuit, main limit, aux limit, or roll out switch •Furnace does not operate, five Red •None flashes on control board •None •Five repeating flashes •Control board fuse, •Limit &
DIAGNOSTIC CHART Refer to the Troubleshooting Chart in the back of this manual for assistance in determining the source of unit operational problems. External Lockout A control lockout resulting from an external fault sensed by the control, such as an unsuccessful recycle or retry period, or a limit trip. Once in External Lockout, the control will shut down for a period of one hour before attempting another trial for ignition. Internal Lockout A failure internal to the control board.
SERVICING S-1 CHECKING VOLTAGE CHECKING THERMOSTAT, WIRING AND ANTICIPATOR WARNING HIGH VOLTAGE DISCONNECT ALL POWER BEFORE SERVICING OR CHANGING ANY ELECTRICAL WIRING. MULTIPLE POWER SOURCES MAY BE PRESENT. FAILURE TO DO SO MAY CAUSE S-3A THERMOSTAT AND WIRING WARNING DISCONNECT ALL POWER BEFORE SERVICING. PROPERTY DAMAGE, PERSONAL INJURY OR DEATH. 1. Remove cover from the Junction Box and gain access to incoming power lines. With Power ON: WARNING LINE VOLTAGE NOW PRESENT 2.
SERVICING S-4 CHECKING TRANSFORMER AND Control CIRCUIT S-16A CHECKING AIR CIRCULATOR BLOWER MOTOR (MULTI-SPEED ECM MOTOR) A step-down transformer 120 volt primary to 24 volt secondary, 40 VA (Heating and Cooling Models) supplies ample capacity of power for either operation. WARNING DISCONNECT ALL POWER BEFORE SERVICING. WARNING HIGH VOLTAGE DISCONNECT ALL POWER BEFORE SERVICING OR CHANGING ANY ELECTRICAL WIRING. MULTIPLE POWER SOURCES MAY BE PRESENT.
SERVICING To determine proper air movement, proceed as follows: 1. With clean filters in the furnace, use a draft gauge (inclined manometer) to measure the static pressure of the return duct at the inlet of the furnace. (Negative Pressure) 2. Measure the static pressure of the supply duct. (Positive Pressure) 3. Add the two (2) readings together for total external static pressure. NOTE: Both readings may be taken simultaneously and read directly on the manometer if so desired.
SERVICING PRIMARY LIMIT CONTROL Primary Limit Control Location (90% Upflow Furnace Shown) The following drawing illustrates the style of limit switches used on the 90% furnaces. If the limit circuit opens five times within a single call for heat, the furnace will go into lockout for one hour. The RED LED will display a FOUR flash code during this time. The control board can be reset by cycling 115 volt power to the furnace.
SERVICING AUXILIARY LIMIT CONTROL VOLT / OHM METER BLOWER HOUSING RED RESET BUTTON AUXILIARY LIMIT CONTROL Auxiliary Limit Control Location COLOR IDENTIFYING TAB Testing Auxiliary Limit Control WARNING HIGH VOLTAGE DISCONNECT ALL POWER BEFORE SERVICING OR INSTALLING THIS UNIT. MULTIPLE POWER SOURCES MAY BE PRESENT. FAILURE TO DO SO MAY CAUSE PROPERTY DAMAGE, PERSONAL INJURY OR DEATH. 1. Remove blower compartment door to gain access to the auxiliary. 2.
SERVICING 302 CHECKING FLAME ROLLOUT CONTROL 7. After check and/or replacement of rollout switch, rein- A temperature activated manual reset control is mounted to the manifold assembly as shown in the following illustration. stall burner compartment door and verify proper unit operation. S-303 INDUCED DRAFT BLOWER Motor FLAME ROLLOUT SWITCHES WARNING HIGH VOLTAGE DISCONNECT ALL POWER BEFORE SERVICING OR INSTALLING THIS UNIT. MULTIPLE POWER SOURCES MAY BE PRESENT.
SERVICING S-306 Two stage gas valves always require 24 volts between common and low fire (main coil) to open. Also, the furnace front cover pressure switch is wired in series with the low (main) solenoid of the gas valve. In the event of a non functioning gas valve, always check the front cover pressure switch. Also see section S-307 on Checking Gas Pressure and section S-310 on Checking Pressure Switches S-305 CHECKING MAIN BURNERS BURNERS Burners have been redesigned for 34.5" chassis furnaces.
SERVICING INLET OUTLET If supply pressure differs from table, make the necessary adjustments to pressure regulator, gas piping size, etc., and/or consult with local gas utility. 5. Turn OFF gas to furnace at the manual shutoff valve and disconnect manometer. Reinstall plug before turning on gas to furnace. 6. Turn OFF any unnecessary gas appliances stated in step 3.
SERVICING 6. Turn on power and close thermostat “R” and “W1” contacts to provide a call for low stage heat. Regulator Vent 7. Measure the gas manifold pressure with burners firing. Adjust manifold pressure using the Manifold Gas Pressure table shown below. 8. Remove regulator cover screw from the low (LO) outlet pressure regulator adjust tower and turn screw clockwise to increase pressure or counterclockwise to decrease pressure. Replace regulator cover screw. 9.
SERVICING e. Remove the 1/8" NPT hose barb fitting from the outlet pressure tap. Replace the outlet pressure boss plug and seal with a high quality thread sealer. S-309 CHECKING FOR FLASHBACK WARNING HIGH VOLTAGE DISCONNECT ALL ELECTRICAL POWER AND SHUT OFF GAS SUPPLY BEFORE SERVICING OR INSTALLING. 2. Turn on gas to furnace and check for leaks. If leaks are found, repair and then reinstall burner compartment door. 3. Turn on electrical power and verify proper unit operation.
SERVICING INDUCED DRAFT BLOWER PRESSURE SWITCH PRESSURE SWITCH HOSE OPEN TO * * ATMOSPHERE * M 1 P 3 O F F * C S-313 CHECKING INTEGRATED IGNITION CONTROL BOARDS 2 ON * * 3. Carry over (lighter tube or cross lighter) obstructed - clean. 4. Main burner orifice(s) deformed, or out of alignment to burner - replace.
R781 R783 K8 E21 E20 E19 HUM E28 E18 XFM R E16 E17 L1 HIGH VOLTAGE DISCONNECT ALL POWER BEFORE SERVICING OR INSTALLING THIS UNIT. MULTIPLE POWER SOURCES MAY BE PRESENT. FAILURE TO DO SO MAY CAUSE PROPERTY ST2 RV2 DAMAGE, PERSONAL INJURY OR DEATH. R89 R88 R94 R95 R96 W 18 R97 R92 Flame current can be measured in two ways: 1. Putting a D.C.
MAINTENANCE WARNING HIGH VOLTAGE DISCONNECT ALL POWER BEFORE SERVICING OR INSTALLING THIS UNIT. MULTIPLE POWER SOURCES MAY BE PRESENT. FAILURE TO DO SO MAY CAUSE PROPERTY DAMAGE, PERSONAL INJURY OR DEATH. CAUTION IF YOU MUST HANDLE THE ITNITOR, HANDLE WITH CARE. T OUCHING THE IG NITOR BODY WITH BARE FINGERS, ROUG H HANDLING, OR VIBRATIO N COULD RESULT IN EARLY IGNITO R FAILURE. O NLY A Q UALIFIED SERVICER SHOULD EVER HANDLE THE IGNITO R.
MAINTENANCE CONDENSATE DRAINAGE SYSTEM (QUALIFIED SERVICER ONLY) The drain tubes, standpipe, and field supplied drain line must be checked annually and cleaned as often as necessary to ensure proper condensate drainage. FLAME SENSOR (QUALIFIED SERVICER ONLY) Under some conditions, the fuel or air supply can create a nearly invisible coating on the flame sensor. This coating acts as an insulator, causing a drop in the flame sensing signal.
MAINTENANCE A / GMEC96 Pressure Switch Trip Points And Usage Chart ID Blower Coil Cover Model *MEC960302BNAB Set Point on Max Make Pressure Low Fire Low Fire High Fire High Fire Pressure Fall Pressure On Switch Set Point on Max Make Set Point on Max Make (PF) W.C. Rise W.C. Part # Pressure Fall Pressure On Pressure Fall Pressure On (PF) W.C. Rise W.C. (PF) W.C. Rise W.C. Part # - 0.67 ± .05 - 0.82 - 1.15 ± .07 - 1.36 0130F00472 - 0.08 ± .04 - 0.
WIRING DIAGRAMS *MEC96 - REV AA YL HIGH FIRE PRESSURE SWITCH C NO NO L N WH DISCONNECT PU 2 CIRCUIT CONNECTOR RD WH HI 3 C 2 PU TO 115VAC/ 1 /60 HZ POWER SUPPLY WITH OVERCURRENT PROTECTION DEVICE OR BR FLAME SENSOR WARNING: DISCONNECT POWER BEFORE SERVICING. WIRING TO UNIT MUST BE PROPERLY POLARIZED AND GROUNDED.
*MEC96 - REV AB WIRING DIAGRAMS GN GRD YL OR PU GY HOT SURFACE IGNITER OR C HIGH FIRE PRESSURE SWITCH C NO NO L RD HI 3 PU WH C 2 DISCONNECT TO 115VAC/ 1Ø /60 HZ POWER SUPPLY WITH OVERCURRENT PROTECTION DEVICE GND L N WARNING: DISCONNECT POWER BEFORE SERVICING. WIRING TO UNIT MUST BE PROPERLY POLARIZED AND DISCONNECT GROUNDED.
