Bryant 345MAV User Manual

NOTE: Read the entire instruction manual before starting theinstallation.Index PageDIMENSIONAL DRAWING...

1. Remove 3 tubes connected to condensate trap.2. Remove trap from blower shelf by gently pushing tabsinward and rotating trap.3. Remove casing hole f

3. Route extended collector box pressure tube behind inducermotor bracket then between inducer motor and pressureswitch.4. Connect collector box press

CAUTION: Do not use this furnace during constructionwhen adhesives, sealers, and/or new carpets are beinginstalled and curing. If the furnace is requi

AIR FOR COMBUSTION AND VENTILATIONI. GENERALProvisions for adequate combustion and ventilation air must beprovided in accordance with Section 5.3, Air

3. When ducts are used, they must be of the same cross-sectional area as the free area of the openings to which theyconnect. The minimum dimension of

II. INSTALLATION ON A CONCRETE SLAB1. Construct hole in floor per dimensions in Fig. 15.2. Place plenum and furnace as shown in Fig. 16.III. INSTALLAT

IV. INSTALLATION IN HORIZONTAL APPLICATIONSThese furnaces can be installed horizontally in either horizontalleft or right discharge position. In a cra

V. FILTER ARRANGEMENTCAUTION: Never operate unit without a filter or withblower access panel removed.Factory-supplied washable framed filters are ship

VII. GAS PIPINGGas piping must be installed in accordance with national and localcodes. Refer to current edition of NFGC. Canadian installationsmust b

Use a separate, fused branch electrical circuit containing a properlysized fuse or circuit breaker for this furnace. See Table 3 for wiresize and fuse

→ Fig. 2—Dimensional DrawingDIMENSIONS (IN.)UNIT SIZE A D E024040 17-1/2 15-7/8 16036040 17-1/2 15-7/8 16024060 17-1/2 15-7/8 16036060 17-1/2 15-7/8 1

Fig. 26—Wiring DiagramA95087PCBBLOWER OFF DELAYSELECTION CHART90 SEC135 SEC180 SEC225 SECGVRHI/LORELAYSEC-1SEC-2WHTPL1321654987LEDTEST/TWINBLOWEROFFDE

NOTE: Use AWG No. 18 color-coded copper thermostat wire forlengths up to 100 ft. For wire lengths over 100 ft, use AWG No.16 wire.III. ACCESSORIES1. E

I. REMOVAL OF EXISTING FURNACES FROMCOMMON VENT SYSTEMSIf furnace being replaced was connected to a common vent systemwith other appliances, the follo

1. Assemble combustion-air inlet pipe.a. Permanently install perforated disk assembly (factory-supplied in loose parts bag) in combustion-air elbowusi

CAUTION: When vent pipe is exposed to temperaturesbelow freezing, such as when it passes through anunheated space or when a chimney is used as a racew

TABLE 4—MAXIMUM ALLOWABLE VENT PIPE LENGTH (FT)ALTITUDE UNIT SIZEVENT PIPEDIAMETER (IN.)NUMBER OF 90° ELBOWS1234560 to 20000240400360401 5 NA NA NA NA

TABLE 4—MAXIMUM ALLOWABLE VENT PIPE LENGTH (FT) ContinuedALTITUDE UNIT SIZEVENT PIPEDIAMETER (IN.)NUMBER OF 90° ELBOWS1234565001 to 6000†0240400360401

WARNING: Vent pipe must be installed and fullyseated against inducer housing. Clamp must be tightenedto prevent any condensate leakage. Failure to fol

16. Use appropriate methods to seal openings where vent pipepasses through roof or sidewall.D. Extended Exposed Sidewall PipesSidewall vent pipe termi

Condensate trap MUST be used for all applications.An external trap is not required when connecting the field drain tothis condensate trap.The field dr

SAFETY CONSIDERATIONSInstalling and servicing heating equipment can be hazardous due togas and electrical components. Only trained and qualified perso

SEQUENCE OF OPERATIONCAUTION: Furnace control must be grounded forproper operation, or control will lock out. Control isgrounded through green wire ro

V. COMPONENT TESTA. Component Test SequenceNOTE: All components are functionally operated except the gasvalve.When component test is initiated, the fo

5. Remove funnel and tube from inducer housing and replacedrain connection cap and clamp.III. PURGE GAS LINESIf not previously done, purge lines after

TABLE 7—MODEL 345MAV ORIFICE SIZE AND MANIFOLD PRESSURE FOR CORRECT INPUT(TABULATED DATA BASED ON 20,000 BTUH PER BURNER, DERATED 2% FOR EACH 1000 FT

TABLE 7—MODEL 345MAV ORIFICE SIZE AND MANIFOLD PRESSURE FOR CORRECT INPUT Continued(TABULATED DATA BASED ON 20,000 BTUH PER BURNER, DERATED 2% FOR EAC

TABLE 7—MODEL 345MAV ORIFICE SIZE AND MANIFOLD PRESSURE FOR CORRECT INPUT Continued (TABULATEDDATA BASED ON 20,000 BTUH PER BURNER, DERATED 2% FOR EAC

CAUTION: DO NOT bottom out gas valve regulatoradjusting screw. This can result in unregulated manifoldpressure and result in excess overfire and heat

EXAMPLE:Btu heating input = Btu/cu ft X cu ft/hrHeating value of gas = 975 Btu/cu ftTime for 1 revolution of 2-cu ft dial = 70 secGas rate = 103 cu ft

return air after furnace has been operating for a period of at least5 minutes. As soon as limit control has shut off burners, return-airopening should

CHECKLIST—INSTALLATIONLOAD CALCULATION____________ Heating Load (Btuh)____________ Cooling Load (Btuh)____________ Furnace Model SelectionVENT PIPINGT

5. Use this procedure for installed and uninstalled (un-grounded) furnaces.6. Before removing a new control from its container, dis-charge your body’s

A94328SERVICE TRAININGPackaged Service Training programs are an excellent way to increase your knowledge of the equipment discussed in this manual, in

2. Condensate Trap Drain TubeThe condensate trap drain connection must be extended forfield attachment by doing the following:a. Determine location of

1. Collector Box Drain TubeConnect collector box drain tube (blue label) to condensatetrap.NOTE: On 17-1/2-in. wide furnaces ONLY, cut tube betweencor

III. DOWNFLOW APPLICATIONSA downflow furnace application is where furnace blower is locatedabove combustion and controls section of furnace, and condi

d. Use inducer housing drain tube (violet label and factory-supplied in loose parts bag) to connect LOWER inducerhousing drain connection to the conde

CAUTION: Local codes may require a drain pan underentire furnace and condensate trap when a condensingfurnace is used in an attic application or over