Bryant 376B User's Manual
Contents
1. HIGH EFFICIENCY gt NOTE Remove the Energy Guide tag from the furnace when the installation is complete NOTE This is a highly specialized piece of equipment Before beginning the installation READ THESE INSTRUCTIONS CAREFULLY AND COMPLETELY INTRODUCTION Before installing the furnace refer to Procedure for Induced Combustion Gas Fired Furnaces packaged with the equipment for information concerning combustion venting piping and other standard installation practices Further reference is made to the current edition of the National Fuel Gas Code NFPA No 54 1984 ANSI Z223 1 1984 The induced combustion vent system of this furnace is designed to operate at zero or negative pressure at the vent connector outlet This furnace therefore complies with the National Fuel Gas Code NFPA No 54 1984 ANSI Z223 1 1984 Part 7 14 3 b This furnace is also listed by A G A for use with the type B1 gas vent as described in the National Fuel Gas Code Part 7 3 2 Each furnace is shipped from the factory completely assem bled with multispeed direct drive blower and wired ready for indoor heating installation All sizes feature a blower con trol center with easy to read low voltage terminal strip to ensure proper connections The output capacity and any representations of efficiency for this product are based on standard Department of Energy test procedures The installed operation may vary depending on installa2. WIRE TWO WRE HEATING Sip AUXILIARY J BOX FLE LD SUPPLIED FUSED DISCONNECT LOW VOLTAGE TERMINAL BLOCK Figure 15 Heating and Cooling Application Wiring Diagram A Adjustment of Blower Speed To change motor speed taps remove the motor tap lead See Table VI and relocate it on the desired terminal on the plug in terminal block speed selector located on the blower TABLE VI SPEED SELECTOR Speed TAP NO Tap No B Automatic Gas Control Valve These units are equipped with an automatic gas control valve If not already checked when lighting the main burner check the proper operation of this valve by moving the room thermostat pointer above and below room temper ature and observing that the main burners light on call for heat there will be a time delay and go off when the pointer is moving below room temperature setting NOTE For ease of adjusting the pilot flame disconnect and tape one power lead at the main gas valve Disconnect ter minal No 1 This will pervent main burner ignition and allow time to adjust the pilot Reconnect the power lead after adjustment XIIL CARE AND MAINTENANCE m FIELD LOW VOLTAGE WIRING FIELD HIGH VOLTAGE WIRING FACTORY LOW VOLTAGE WIRING FIE LD SUPPLIED FUSED DISCONNECT THREE PHASE SINGLE PHASE CONDENSING UNIT NOTE IF ANY OF THE ORIGINAL WIRE AS SUPPLIED MUST BE REP
3. the heat exchanger because of carbon deposits soot etc proceed as follows NOTE Deposits of soot and carbon indicate a problem exists and needs correcting Corrective action must be taken to correct the problem 1 Turn off gas and power to furnace 2 Remove control and blower access doors 3 Remove vent pipe enclosure and disconnect vent pipe from relief box 4 Remove four screws that secure relief box to blower shelf _5 Disconnect two wires from safeguard switch 6 Disconnect wire harness edge connector from side of inducer control box A77007 Figure 17 Dual Blower With Left Hand Housing and Wheel Removed a 7 Remove eight screws that secure flue collector box to center panel Use care not to damage sealant 8 Remove complete inducer assembly from furnace exposing flue openings 9 Remove flue choke 10 Using field provided small wire brush steel spring cable reversible electric drill and vacuum cleaner clean cells a Assemble wire brush and steel spring cable 1 Use 4 feet of 1 4 in diameter high grade steel spring cable commonly known as drain cleanout or Roto Rooter cable 2 Use 1 4 in diameter wire brush commonly known as 25 caliber rifle cleaning brush NOTE The items called for in steps 1 and 2 can be pur chased at a local hardware store 3 Insert twisted wire end of brush into end of spring cable and crimp tight with crimping tool or strike with ball peen hamme
4. Control Board 10B2 Connector Edge Inducer Control Board 7 CKT 10B3 Connector Edge Inducer Control Board 2 CKT 10B4 Connector Pilot 10B5 Factory Test Points 10B6 Connector Blower Motor 11B Fuse In Line 2 Amp When Used 11C Link Fusibie Overtemperature 3 Required 11E Ground Equipment TP 1 Test Point Factory Wiring 120 VAC Factory Wiring 24 VAC Conductors on 6C1 Furnace Control Board Conductors on 6C2 Inducer Control Board Screw Termina for Field Wiring C 1 4 inch Quick Connect Terminals RETURN AIR PLENUM INSTALLATION OSITIO i l 1 N ACCESS PANEL A82179 Figure 11 Position of Filters IX SEQUENCE OF OPERATION Using the schematic wiring diagram Figure 12 trace the sequence of operation for the heating cycle is as follows 1 When the blower door is in place 120 volts is supplied through blower door interlock switch 9G Transformer 1A is energized supplying 24 volts to heating blower relay coil 2E which opens normally closed blower relay contacts 2E in the low speed circuit of blower motor 3D TO 120VAC FIELD CONNECTIONS SCHEMATIC NATL amp PROP LIBL 4 fon2 5 2b 1NB3 1 1083 2 1082 1 10B1 7 aX TECT ROME ESC QD WIR CLEANER WHEN USED In 120 VAC ARR 2 THI 11C I0BI Ho SEC 1 10B1 5 WHEN USED J 24 VAC USEC lt 3 SOLID STATE TIME DELAY RELAY iB 2E l ROY l N l OFF i SI
5. ES OF THE FURNACE JACKET AND BUILDING JOISTS STUDS OR FRAMING FLUE VENT a pA T N MI N a SEDIMENT TRAP A82178 Figure 8 Typical Attic Installation ae ae above the louvered control panel Extend the sheet metal shield over the furnace top far enough to cover the gas pipe entry hole l VIH FILTER ARRANGEMENT The two factory supplied filters are shipped in the blower compartment After the return air duct has been connected to the furnace install the filters in a V formation inside the return air plenum See Figure 10 and Table V for horizontal applications See Figure 11 for downflow applications A82173 Figure 10 Horizontal Filter Arrangement TABLE V FILTER RETAINER Furnace Casing Width a a Seca 14 3 16 15 3 16 17 1 2 14 1 2 13 9 16 LEGEND 1A Transformer 120 VAC 24 VAC 2D Relay Inducer Motor DPST N O 2E Relay Heating Blower HFR SPST N C 2F Reiay Cooling Blower CFR DPDT 3A Motor Inducer 3D Motor Blower 4A Capacitor Run SF Valve Gas Redundant 6C3 Lockout Module When Used 6F Generator Spark Solid State 6H Switch Pilot Flame Sensing SPDT 7H1 Switch Limit SPST N C 7H2 Switch Draft Safeguard SPST N C Manual Reset 7H3 Switch Auxiliary Limit SPST N C Manual Reset When Used 7P Pressure Switch N O 7V Switch Flow Sensing SPDT 9G Switch Blower Door Interlock SPST N O 10B1 Connector Edge Furnace
6. GNAL Crna Fi TP SIGNAL uA aat ee se a a EEE aS RGN ag RAEN Be J 2D C2ZOZAL LL V3 HIH 4 10B2 4 M 7 1021 3 DI nl T S 2n f E gs 24 pi 2 D4 D3 Ly sp 73 WHEN 4 USED j L 1OBL G toB2 2 f 0 OD KO AT S aD oi eee TH3 USED A AUX LIMIT al WHEN USED Ss A 7 oe T A85063 Figure 12 Line to Line Wiring Diagram 2 2 The wall thermostat calls for heat closing the R and W circuit This closed circuit supplies power to the 24 volt safety circuit containing limit switch 7H1 fusible link 11C manual reset draft safeguard switch 7H2 and manual reset auxiliary switch 7H3 3 Simultaneously the pick coil of gas valve 5F spark generator 6F and inducer motor relay coil 2D are ener gized Inducer motor relay contacts 2D in the 120 volt circuit close starting inducer blower motor 3A Also another set of contacts in inducer motor relay 2D close in the 24 volt circuit and lock in inducer motor relay coil 2D The coil is locked in until the R and W circuit or safety circuit opens 4 When the pick coil of gas valve 5F is energized gas flows to the pilot The pilot gas is ignited by a spark produced by spark generator 6F Simultaneously inducer motor 3A comes up to speed actuating flow sensing switch 7V energizing the hold coil of gas valve 5F The pick coil of gas valve 5F and spark generator 6F are deenergized when the contacts of pilot flame sensing switch 6H move fr
7. LACED USE SAME TYPE OR EQUIVALENT WIRE A78461 6 T REGULATOR ADJUSTMENT PRESSURE TAP PILOT TUBE CONN PILOT ADJUSTMENT MANUAL ON OFF A82222 Figure 16 Redundant Automatic Gas Control Valve n woene nn ee e n TIELDIRE en ed EETA E Tre a a n Tu p ee REHAR PEBRE Porre ar Far RATAA Tg SS Fe er Sa FF Se Shwe ee n i el a r Zan Tee E For continuing high performance and to minimize possible equipment failure it is essential that periodic maintenance be performed on this equipment Consult your local Dealer as to the proper frequency of maintenance and the availabil ity of a maintenance contract The ability to properly perform maintenance on this equip ment requires certain mechanical skills and tools If you do not possess these contact your Dealer for maintenance The minimum maintenance that should be performed on this equipment is as follows i Check and clean or replace air filter each month or as required 2 Check blower motor and wheel for cleanliness and lubri cation each heating and cooling season Clean and lubricate as necessary 3 Check electrical connections for tightness and controls for proper operation each heating season Service as necessary A Air Filter Each furnace accommodates two filters which are installed in the return air duct See Figures 10 and 11 To clean or replace the filters proceed as foll
8. filter retainers as indicated in Figure 10 and Table V before connecting return air duct to furnace i NOTE For ease of servicing a return air filter can be installed in a common return air grille The air velocity rat ing must not exceed 300 ft min for disposable filters The air velocity through permanent type filters shall not exceed the manufacturer s recommendation d Using appropriate fasteners for type of duct being used connect return air duct to furnace l 4 Install 24 x24 in sheet metal shield on platform in front of louvered control panel as shown in Figure 8 Vil CRAWL SPACE INSTALLATION The 376B Furnace can be installed horizontally with either the LH or RH side up In a crawl space the furnace can either be hung from the floor joist or installed on suitable blocks or pad The furnace can be suspended from each cor ner by hanger bolts Four each 3 8 in all thread rod cut to desired length 1 x 3 8 flat washer 3 8 lockwasher and 3 8 nut Dimples are provided for hole locations See Figure 3 NOTE Use Type B1 vent in a concealed space The crawl space installation is very similar to the attic therefore refer to Division VI Section B steps 1 2 and 3 The installation of a sheet metal shield in front of the lou vered control panel is covered in step 4 For a crawl space installation this same sheet metal shield must be installed LINE CONTACT ONLY PERMISSIBLE BETWEEN ONS OF THE TOP AND TWO SID
9. install flue choke Be sure all screws are in place and tight 13 Clean and replace flue collector assembly making sure all eight screws are secure 14 Replace four screws that secure the relief box to blower shelf 15 Reconnect two wires to safeguard switch 16 Reconnect wire harness edge connector to side of inducer control box 17 Reconnect vent pipe to relief box reinstall pipe enclosure 18 Replace blower door only 19 Turn on power and gas 20 Set thermostat and check furnace for proper operation 21 Check for gas leaks 22 Replace control door D Pilot Check the pilot and clean if necessary at the beginning of each heating season The pilot flame should be high enough for proper impingement of the safety element and to light the burners Remove the accumulation of soot and carbon from the safety element or sensing probe See Figure 19 and check electrode position E Electrical Controls and Wiring NOTE There may be more than one electrical supply to unit With power disconnected to unit check all electrical connec tions for tightness Tighten all screws on electrical connec tions If any smoky or burned connections are noticed dis assemble the connection clean all parts and strip wire and reassemble properly and securely Electrical controls are dif ficult to check without proper instrumentation therefore reconnect electrical power to unit and observe unit through one complete o
10. ir ducts or a flue or vent that could affect its operation and prevent it from properly controlling the THERMOSTAT TERMINALS AROUND MMETER FROM UNIT LOW VOLTAGE TERMINAL BLOCK OF FURNACE 5 0 AMPS ON AMMETER 10 TURNS AROUND JAWS EXAMPLE 0 5 AMPS FOR THERMOSTAT SETTING A80201 Figure 13 Amp Draw Check With Ammeter 5 room temperature Any hole in the plaster or panel through which the wires pass from the thermostat should be ade quately sealed with suitable material to prevent drafts from affecting the thermostat C Blower Control Center Each furnace features a blower control center This will aid the installer and serviceperson when installing and servic ing the unit A low voltage terminal board is marked for easy connection of field wiring See Figure 14 XI STARTUP AND ADJUSTMENT In addition to the following information refer to Proce dures for Induced Combustion Gas Fired Furnaces pack aged with the unit NOTE The furnace blower door must be in place to complete the 115 volt circuit to the furnace The gas service pressure must not exceed 14 in we 8 1 ounces for natural gas NOTE The gas valve regulator has been factory set at 3 5 in we for natural gas Refer to Procedure for Induced Combustion Gas Fired Furnaces for readjusting when checking input f Figure 14 Blower Control Center 83136 TERMINALS FOUR
11. n the furnace is installed in the horizontal posi tion with RH discharge air low voltage wire connections can be made easier by removing the two control box mount ing screws and letting the control box turn so that the low voltage screw terminals are visible Be sure to reinstall the control box after the connections are made Oo NOTE Use AWG No 18 color coded copper thermostat wire for lengths up to 100 ft Above 100 ft use AWG No 16 wire IMPORTANT The thermostat heat anticipation must be set to match the amp draw of the gas valve and electrical com ponents in the R W circuit Accurate amp draw readings can be obtained at thermostat subbase terminals R amp W Figure 13 illustrates an easy method of obtaining the actual amp draw The amp reading should be taken after the blower motor has started The room thermostat should be located where it will be in the natural circulation path of room air Avoid locations where the thermostat would be exposed to cold air infiltra tion drafts from windows doors or other openings leading to the outside or exposed to air currents from warm or cold air registers or to exposure where the natural circula tion of the air is cut off such as behind doors above or below mantels shelves etc The thermostat should not be exposed to heat from nearby fireplaces radios televisions lamps or rays from the sun Nor should the thermostat be mounted on a wall containing pipes or warm a
12. om the normally closed posi tion breaking the circuit to the pick coil and spark gen erator In approximately 50 to 60 seconds the nor mally open pilot flame sensing contacts close making the circuit to the MGV Main Operator of gas valve 5F Gas valve 5F opens in approximately 10 seconds allowing gas flow to the main burners which are ignited by pilot 6H Simultaneously time delay circuit 11L in the blower control center is energized Approxi _ mately 50 seconds after gas valve 5F opens heating relay coil 2E is deenergized which closes the 120 volt contacts of heating relay 2E starting blower motor 3D on its heating speed 5 When the thermostat is satisfied the circuit between R and W is broken deenergizing gas valve 5F inducer motor relay 2D and the solid state time delay circuit on the printed circuit board The gas flow stops imme diately to the pilot and main burners After approxi mately 105 seconds heat relay 2E is energized and blower motor 3D stops 7 NOTE After a brief interruption of either electric or gas sup ply the furnace will not resume operation until the contacts of pilot flame sensing switch 6H move from the normally open to the normally closed position Cooling Cycle 1 The wall thermostat calls for cooling 2 The R G and Y circuits are energized Simultaneously the R and Y circuit starts the outdoor condensing unit and the R and G circuit energizes cooling relay coil 2F which clo
13. ows 1 Disconnect electrical power before removing access panel 2 Remove upper access panel 3 Reach up behind top plate tilt filters toward center of return air plenum remove filters and replace or clean as needed 4 Furnaces are equipped with permanent washable fil ters Clean those filters as follows a Clean with tap water b Rinse and let dry No oiling or coating of filters i required c Reinstall filters with cross hatch binding facing blower _ B Blower Motor and Wheel 1 Remove blower access panel 2 Remove vent pipe enclosure 3 Disconnect vent pipe and remove short piece of pipe from furnace 4 Disconnect wires from auxiliary limit on blower housing NOTE For ease of blower removal it may be necessary to remove the control box on some sizes 5 Remove blower assembly from furnace 6 Remove motor from blower housing 7 Lubricate motor using good grade of SAE 20 nondeter gent motor oil Put one teaspoon 5cc 3 16 oz or 16 to 25 drops in each oil port 8 Remove blower wheel from housing and clean by using vacuum with soft brush attachment Care must be exercised not to disturb balance weights clips on blower wheel vanes ttt tn 9 Reassemble furnace by reversing above procedures When a more detailed servicing procedure is required see the furnace Service Manual available from your Dealer or Distributor C Cleaning Heat Exchanger If it becomes necessary to clean
14. perating cycle If there are any discrepancies in the operating cycle contact your Dealer and request service l 8I Mm A79080 Figure 19 Position of Electrode to Pilot i
15. r Tightness is very important 4 Remove metal screw fitting from wire brush to allow insertion into cable b Clean each heat exchanger cell 1 Attach variable speed reversible drill to end of spring cable end opposite brush 2 Insert brush end of cable into upper opening of cell and slowly rotate with drill Do not force cable Gradually insert at least 3 feet of cable into two upper passes of cell See Figure 18 3 Work cable in and out of cell three of four times to obtain sufficient cleaning Do not pull cable with great force Reverse drill and gradually work cable out 4 Remove burner assembly and flame radiators Identify gas valve leads 5 Insert brush end of cable in lower opening of cell and proceed to clean two lower passes of cell in same manner as two upper passes 6 Repeat the foregoing procedures until each cell in furnace has been cleaned 7 Using vacuum cleaner remove residue from each cell 8 Using vacuum cleaner with soft brush attach ment clean burner assembly A82181 Figure 18 Cleaning Heat Exchanger Cell 9 Reinstall flame radiators and burner assembly Care must be exercised to center the flame radi ators in the cell openings Refer to furnace wir ing diagram when reconnecting gas valve leads 11 After cleaning flue openings check sealant on flue col lector to ensure that it has not been damaged If new sealant is needed contact your Distributor 12 Re
16. r base in alcoves attics crawl spaces basements closets or utility rooms The design of this furnace line is not A G A certified for installation in mobile homes recreation vehi cles or outdoors BDP Company TABLE II DIMENSIONS In Inches 4 4 038076 ire 1578 1e T 16 E 3 060115 24 1 2 22 13 16 DIMPLES TO 5 DRILL HOLES 8 FOR HANGER BOLTS BOTH SIDES A82171 AIRFLOW 3 E 4 OUTLET A Figure 3 Dimensional Drawing TABLE III RATINGS AND PERFORMANCE emperature Heating SIZE Capacity Rise External Static Ft Min Buthtt Range Pressure 024040 48 000 39 000 50 80 _ 024055 67 000 56 000 40 70 835t 70 oa8075 90 000 75000 4 70 015 m 05 948095 114000 000 5s 85 o2 128 05 i 060095 114 000 95 000 55 85 7350 060715 137 000 115 000 45 75 0 20 The above gas inputs are certified for altitudes to 2000 ft For elevations above 2000 ft reduce input 4 for each 1000 ft above sea level t Determined by U S Government tests tTentative rating Installation comprises the following To perform these sections or installation steps refer to the appropriate sections of Procedures for Induced Com i neater bustion Gas Fired F booklet packaged with thi II Location Ventilation and Air for Combustion POT SARS a t a 5 III Gas Pipi a Gas Pipin i i d For accessory ins
17. ses normally open contacts 2F energizing the cooling speed winding of motor 3D and opening the normally closed contacts of cooling relay 2F X ELECTRICAL CONNECTIONS A Line Voltage Wiring IMPORTANT Before proceeding with the electrical con nections make certain that voltage frequency and phase correspond to that specified on the unit rating plate Also check to be sure that the service provided by the utility is sufficient to handle the additional load imposed by this equipment Refer to the unit rating plate for equipment elec trical requirements 7 See Figure 15 for wiring diagram showing the proper field high and low voltage wiring Make all electrical connections in accordance with the National Electrical Code and any local codes or ordinances that might apply Use a separate fused branch electrical circuit containing a properly sized fuse or HACR type circuit breaker for this furnace A disconnecting means must be located within sight of and readily accessible to the furnace The blower door switch may be acceptable in some areas as a discon necting means If line voltage wiring to the unit is encased in a nonmetallic sheath connect the incoming ground wire to the grounding wire inside the furnace J box If metallic conduit is used it will serve as the ground B Low Voltage Wiring Make field low voltage connections at the lew voltage termi nal strip See Figure 15 NOTE Whe
18. sions in Table I of Installation Instructions packaged with combustible floor base If this requires cutting of a floor joist tie ends of cut joist into adjacent joists so that proper floor support will be maintained 3 Assemble and install combustible floor base per instructions packaged with base 4 When completed combustible floor base plenum and furnace or coil casing when used should be installed as shown in Figure 7 VI HORIZONTAL ATTIC INSTALLATION The 376B Furnace can be installed horizontally on either the LH or RH side A typical attic installation is shown in Fig ure 8 NOTE The National Fuel Gas Code requires the use of a type B1 vent in an attic or concealed space A Construct a working platform 1 Place working platform in location where all required furnace clearances are obtainable See Table I 2 Use materials in platform that will support installer and service persons 3 Secure platform to building joists A82172 Figure 9 Duct Flange Installation B Install furnace 1 Position furnace in desired location 2 Connect gas supply pipe See Figure 8 for typical pip ing entry It is important to install a sediment trap in the gas pipe riser 3 Connect supply and return air ducts a Install field supplied duct flanges as shown in Fig ure 9 b Using appropriate fasteners for type of supply air duct being used connect duct to furnace c Install field supplied
19. tallation details refer to applicable instal IV Venting sna lation literature V Supply Air Plenum Installation Downflow VI Attic Installation VII Crawl Space Installation V SUPPLY AIR PLENUM INSTALLATION DOWNFLOW A installation on a concrete slab Vill Filter Arrangement opening in furnace bottom IX Sequence of Operation 2 Construct hole in floor per dimensions in Figure 4 and X Electrical Connections Table IV XI Startup and Adjustment 3 Place plenum and furnace as shown in Figure 5 XII Care and Maintenance B Installation on a combustible floor 1 Read Installation Instructions packaged with combus tible floor base r fad 4 oea B HOLE IN FLOOR A73382 A73383 Figure 4 Floor Opening for Concrete Slab Figure 5 Furnace on a Concrete Slab 7 TABLE IV OPENING DIMENSIONS Furnace Casing A ee ae Width Heat Only Heat Cooi 14 3 16 17 1 2 _24 1 2 These dimensions apply when a Model 518A Evaporator Coil casing is to be installed Figure 6 Combustible Floor Base eee i A78650 sze aA B_J E Vent Conn 024040 14 3 16 12 9716 12 1116 4 024055 14 3 16 12 9716 12 11 16 1 See Figure 3 for dimensions and location of supply air Q OR COIL CASING L WHEN USED COMBUSTIBLE FLOOR BASE A78651 Figure 7 Furnace Plenum and Base Installed on a Combustible Floor 2 Cut and frame hole in floor per dimen
20. tion weather or other factors TABLE I CLEARANCES In Inches DOWNFLOW In Alcove or Closet Sides Single Wall Vent Type B1 Double Wail Vent Front Single Wall Vent Type B1 Double Waill Vent Vent Single Wall Type B1 Double Wall HORIZONTAL In Alcove Sides per Top Single Wall Vert Type B1 Double WallVent oo o ooo ee DEEN SO RR TENT Vent Singie Wal STE a Type B1 Double Wall i HORIZONTAL in Closet Top Single Wall Vent Type B1 Double Wall Vent Front Single Wall Vent Type B1 Double Waill Vent Vent Single Wall Type B1 Double Wall Provide a 30 in service clearance in front of the furnace Tindicates supply or return sides when furnace is in the horizontal position l 2 it i installation operation gt and maintenance instructions DOWNFLOW HORIZONTAL INDUCED COMBUSTION FURNACE Series A a Sizes 040 thru 115 40376DP5 B 9 1 85 Cancels 39376DP5 A EFFICIENCY RATING CERTIFIED A83215 z To eo T a or Asha Leer Ss ESS S SESS SESE ES NEENA H SeseSac The design of the downflow horizontal gas fired furnace is A G A certified for natural and LP propane gas and for installation on combustible flooring with optional floo
Download Pdf Manuals
Related Search