Bryant 345MAV, User'S Information Manual

2

WELCOME TO A NEW GENERATION 
OF COMFORT

Congratulations! In light of rising energy costs, the 345MAV 
Multipoise Condensing Gas Furnace is among the soundest 
investments today’s homeowner can make.

Your new furnace is truly a triumph of technology in home 
heating. A revolutionary design employs 2 heat exchangers 
to “squeeze” out the maximum amount of heat from the fuel 
consumed. In fact, your new furnace is so efficient, 90%* of 
the heat generated during combustion is captured and deliv-
ered inside your home. That is more than a 33%* increase 
in heating efficiency over conventional furnaces.

The furnace is among the most energy-efficient furnaces you 
can buy today. It is also among the safest and most depend-
able. We are proud of the technological advances incorpo-
rated into the design of this furnace. With only minimal care, 
your new furnace will deliver many years of money-saving 
home comfort and enjoyment. Spend just a few minutes with 
this manual to learn the operation of your new furnace and 
the small amount of maintenance it takes to help keep it 
operating at peak efficiency year after year.

* The output capacity and any representations of efficiency for this furnace are based on stan-

dard U.S. Department of Energy test procedures.

MODEL 345MAV FURNACE

TABLE OF CONTENTS

WELCOME TO A NEW GENERATION OF COMFORT

. . . . . . . .2

GENERAL FURNACE SAFETY

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

FURNACE COMPONENTS

 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

SAFETY CONSIDERATIONS

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4

BEFORE STARTING YOUR FURNACE

. . . . . . . . . . . . . . . . . . . . . . . .4

STARTING AND SHUTTING DOWN YOUR FURNACE

. . . . . . . .4

Steps for Starting Your Furnace . . . . . . . . . . . . . . . . . . . . . . . . .  4,5

Shutting Down Your Furnace . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

PERFORMING ROUTINE MAINTENANCE

. . . . . . . . . . . . . . . . . . .6

Filtering Out Trouble . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  6,7

COMBUSTION AREA AND VENT SYSTEM

 . . . . . . . . . . . . . . . . . . .7

Heading South For the Winter . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

A CHECK-UP CHECKLIST

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

BEFORE YOU REQUEST A SERVICE CALL

 . . . . . . . . . . . . . . . . . .9

INSTALLATION DATA

 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  12

GENERAL FURNACE SAFETY

  1.

Combustible Materials, Gasoline Warning

. . . . . . . . . . . . . . . . . . 1,4

  2.

Furnace Must be Kept Free and Clear of Insulating 

Material Warning

 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  4

  3.

Furnace Needs Air for Combustion and Ventilation Warning

 . .  4

  4.

Starting (Lighting) and Shutting Down the 
Furnace Warning

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4–6

  5.

Proper Furnace Shutdown Procedures

. . . . . . . . . . . . . . . . . . . . . .  6

  6.

Flood Damage Warning

 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  1

  7.

Fire or Explosion Hazard Warning

 . . . . . . . . . . . . . . . . . . . . . . . . .  1

  8.

Carbon Monoxide Warning

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  1

  9.

Service and Maintenance Electrical Hazard Warning

. . . . . . . . .  6

10.

Improper Vent Warning

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  8

11.

Sharp Edges Caution

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  6

12.

No Filter Caution

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  6

13.

Filter Rod Modification Caution

. . . . . . . . . . . . . . . . . . . . . . . . . . . .  8

14.

Dirt, Rust, or Accumulation Caution

. . . . . . . . . . . . . . . . . . . . . . . .  8

15.

Freeze Damage Caution

 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6,8

16.

Loud Noise Caution

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  8

17.

Antifreeze Caution

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  8

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CERTIFIED

As an ENERGY STAR® 
Partner, Bryant Heating 
& Cooling Systems  
has determined that 
this product meets the 
ENERGY STAR® 
guidelines for energy 
efficiency.