Servicing Hot Surface Igniter - Bryant 350MAV Service And Maintenance Procedures Manual

14. Check furnace operation through 2 complete heat operating
cycles. Check area below inducer housing, vent pipe, and
condensate trap to ensure no condensate leaks occur. If
leaks are found, correct the problem.
WARNING: FIRE OR EXPLOSION HAZARD
Failure to follow the safety warnings exactly could result
in serious injury, death, or property damage.
Never test for gas leaks with an open flame. Use a
commercially available soap solution made specifically
for the detection of leaks to check all connections. A fire
or explosion may result causing property damage, per-
sonal injury, or loss of life.
15. Check for gas leaks.
16. Replace main furnace door.
VI. SERVICING HOT SURFACE IGNITER
The igniter does NOT require annual inspection. Check igniter
resistance before removal.
1. Turn off gas and electrical supplies to furnace.
Furnace is shipped from factory in upflow configuration. Pressure tube and drain tube routing MUST match the diagrams below.
Condensate Trap; Factory Installed
in Blower Shelf
(Blower access panel removed)
COLLECTOR BOX TUBE
(PINK)
COLLECTOR BOX TUBE
(GREEN)
INDUCER HOUSING (MOLDED) DRAIN TUBE
(BEHIND COLLECTOR BOX DRAIN TUBE)
COLLECTOR BOX DRAIN TUBE
(BLUE)
FIELD-INSTALLED
FACTORY -SUPPLIED DRAIN TUBE
COUPLING (LEFT DRAIN OPTION)
FIELD-INSTALLED FACTORY -SUPPLIED
DRAIN TUBE
Condensate Trap on
LEFT Side
COLLECTOR BOX
TUBE (GREEN)
COLLECTOR BOX DRAIN TUBE
(BLUE & WHITE STRIPED)
COLLECTOR BOX
EXTENSION TUBE
CONDENSATE TRAP
BURNER ENCLOSURE PRESSURE
REFERENCE TUBE ASSEMBLY
INDUCER HOUSING DRAIN TUBE (VIOLET)
Tube location when used on
HORIZONTAL - LEFT application
PLUG
CAP
BURNER ENCLOSURE
PRESSURE REFERENCE
TUBE ASSEMBLY
COLLECTOR BOX
EXTENSION TUBE
CONDENSATE TRAP
COLLECTOR BOX EXTENSION DRAIN TUBE
NOTE:
1. All tubing must be connected securely and routed to avoid kinks and traps.
2. Pressure tubing must always slope away from pressure switch to collector box connection as shown.
3. HORIZONTAL-LEFT installations require the collector box pressure tube to be relocated between the inducer housing and the blower shelf to
prevent a trap. Refer to the Installation Instructions for further details.
Tube location when used in UPFLOW application
BURNER ENCLOSURE
PRESSURE REFERENCE
TUBE ASSEMBLY
CAP
PLUG
COLLECTOR BOX DRAIN
(BLUE & WHITE STRIPED)
CONDENSATE TRAP
FACTORY -SUPPLIED
DRAIN TUBE COUPLING
(RIGHT DRAIN OPTION)
FIELD-INSTALLED
FACTORY -SUPPLIED 1/2-IN.
CPVC STREET ELBOWS (2)
FOR LEFT DRAIN OPTION
Tube location when used in DOWNFLOW application
COLLECTOR BOX
CAP
DRAIN TUBE (BLUE)
PLUGGED END
PLUG
COLLECTOR BOX
EXTENSION TUBE
COLLECTOR BOX
TUBE (PINK)
COLLECTOR BOX DRAIN TUBE
(BLUE & WHITE STRIPED)
COLLECTOR BOX
INDUCER HOUSING
COLLECTOR BOX
DRAIN TUBE (BLUE)
DRAIN TUBE COLLECTOR BOX TUBE (PINK)
RELOCATE TUBE BETWEEN BLOWER
COUPLING
SHELF AND INDUCER HOUSING FOR
040,060, AND 080 HEATING INPUT
FURNACES
Fig. 8—Furnace Pressure and Drain Tubing Diagram
2. Remove main furnace door.
3. Disconnect igniter wire connection.
4. Check igniter resistance.
a. Using an ohm meter, check resistance across both igniter
leads in connector.
b. Cold reading should be between 45 ohms and 90 ohms.
c. If ohm reading is higher than 110 ohms, igniter is
cracked and must be replaced.
5. Remove igniter assembly.
CAUTION: Allow igniter to cool before removal. Nor-
mal operating temperatures exceed 2000°F.
a. Do not remove igniter from bracket while assembly is in
furnace. Using a 1/4 in. nutdriver, remove screw secur-
ing bracket and igniter assembly to bottom of burner
box. The screw in the bracket is always located toward
outside of burner box. The screw may be hidden by inlet
TUBE ROUTING
COLLECTOR BOX TUBE
(PINK)
TUBE
COLLECTOR BOX TUBE (GREEN)
COLLECTOR BOX DRAIN TUBE
(BLUE)
FIELD-INSTALLED
CONDENSATE TRAP
COLLECTOR BOX DRAIN
TUBE
(BLUE & WHITE STRIPED)
INDUCER HOUSING DRAIN
TUBE (VIOLET)
DRAIN TUBE COUPLING
DRAIN TUBES ROUTED IN
FRONT OF GAS VALVE
Tube location when used on
HORIZONTAL - RIGHT application
COLLECTOR BOX DRAIN TUBE
(BLUE)
PLUG
TUBE (GREEN)
CAP
DRAIN TUBE
(VIOLET)
COLLECTOR BOX
TUBE (GREEN)
COLLECTOR BOX DRAIN TUBE
(BLUE AND WHITE STRIPED)
—7—
Condensate Trap on LEFT
Side Optional
BURNER ENCLOSURE
PRESSURE REFERENCE
TUBE ASSEMBLY
CAP
PLUG
COLLECTOR BOX DRAIN TUBE
(BLUE & WHITE STRIPED)
INDUCER HOUSING DRAIN TUBE
(VIOLET)
Condensate Trap on
RIGHT Side
PLUG
CAP
COLLECTOR BOX DRAIN TUBE
(BLUE)
COLLECTOR BOX TUBE
(PINK)
COLLECTOR BOX TUBE
(GREEN)
COLLECTOR BOX EXTENSION TUBE
BURNER ENCLOSURE PRESSURE
REFERENCE TUBE ASSEMBLY
CONDENSATE TRAP
COLLECTOR BOX
EXTENSION DRAIN TUBE
GAS VALVE
COLLECTOR BOX EXTENSION TUBE
COLLECTOR BOX TUBE (PINK)
AUXILIARY "J" BOX RELOCATED HERE
BURNER ENCLOSURE
PRESSURE REFERENCE
TUBE ASSEMBLY
COLLECTOR BOX
EXTENSION TUBE
CONDENSATE TRAP
INDUCER HOUSING DRAIN TUBE (VIOLET)
324999-201 REV. C
A00308