International comfort products R9MSB, Service And Technical Support Manual

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440 04 6601 03 19 Specifications subject to change without notice.
6. Disconnect the condensate trap relief hose from
collector box port and condensate trap.
NOTE : If condensate has a heat pad attached to the trap,
trace the wires for the pad back to the connection point and
disconnect the wires for the heat pad.
7. Remove the screw that secures the condensate trap
to the collector box, remove the trap and set aside.
8. Remove the trap gasket from the collector box if it did
not come off when the trap was removed.
9. Discard the old trap gasket.
10. Rinse condensate trap in warm water until trap is
clean.
11. Flush condensate drain lines with warm water.
Remember to check and clean the relief port on the
collector box.
12. Shake trap dry.
13. Clean port on collector box with a small wire.
To re-install Condensate Drain and Trap:
1. Remove adhesive backing from condensate trap
gasket
2. Install gasket on collector box
3. Align the condensate trap with the drain opening on
the collector box and secure the trap with the screw
4. Attach the relief hose to the relief port on the
condensate trap and collector box.
5. Secure tubing to prevent any sags or traps in the
tubing.
6. Connect condensate drain elbow or drain extension
elbow to the condensate trap
7. Connect the leads of the condensate heat pad (if
used)
8. Connect external drain piping to the condensate drain
elbow or drain extension pipe.
9. Turn gas on at electric switch on gas valve and at
external shut-off or meter
10. Turn power on at external disconnect, fuse or circuit
breaker.
11. Run the furnace through two complete heating cycles
to check for proper operation
12. Install control door when complete.
Checking Heat Pad Operation (If Applicable)
In applications where the ambient temperature around the
furnace is 32 _ F (0 _ C) or lower, freeze protection measures
are required. If this application is where heat tape has been
applied, check to ensure it will operate when low
temperatures are present.
NOTE : The Heat Pad, when used, should be wrapped
around the condensate drain trap. There is no need to use
heat tape within the furnace casing. Most heat tapes are
temperature activated, and it is not practical to verify the
actual heating of the tape. Check the following:
1. Check for signs of physical damage to heat tape such
as nicks, cuts, abrasions, gnawing by animals, etc.
2. Check for discolored heat tape insulation. If any
damage or discolored insulation is evident, replace
heat tape.
3. Check that heat tape power supply circuit is on.
Cleaning Heat Exchangers
The following items must be performed by a qualified
service technician.
Primary Heat Exchangers
If the heat exchangers get an accumulation of light dirt or
dust on the inside, they may be cleaned by the following
procedure:
NOTE : If the heat exchangers get a heavy accumulation of
soot and carbon, both the primary and secondary heat
exchangers should be replaced rather than trying to clean
them thoroughly due to their intricate design. A build − up of
soot and carbon indicates that a problem exists which
needs to be corrected, such as improper adjustment of
manifold pressure, insufficient or poor quality combustion
air, improper vent termination, incorrect size or damaged
manifold orifice(s), improper gas, or a restricted heat
exchanger (primary or secondary). Action must be taken to
correct the problem.
1. Turn off gas and electrical supplies to furnace.
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow this warning could result in personal
injury or death, or property damage.
Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF
position and install a lockout tag. There may be more
than one disconnect switch. Lock out and tag switch
with a suitable warning label. Verify proper operation
after servicing. Always reinstall access doors after
completing service and maintenance.
!
WARNING
ELECTRICAL SHOCK AND FIRE HAZARD
Failure to follow this warning could result in personal
injury, death, and/or property damage.
Turn off the gas and electrical supplies to the furnace
and install lockout tag before performing any
maintenance or service. Follow the operating
instructions on the label attached to the furnace.
!
WARNING
2. Remove control door.
3. Disconnect wires or connectors to flame rollout
switch, gas valve, igniter, and flame sensor.
4. Using backup wrench, disconnect gas supply pipe
from furnace gas control valve.
5. Remove two screws attaching top filler plate and
rotate upwards to gain access to screws attaching
burner assembly to cell panel.
6. Remove screws attaching burner assembly to cell
panel. (See Figure 14.)
NOTE : Burner cover, manifold, gas valve, and burner
assembly should be removed as one assembly.
7. Clean heat exchanger openings with a vacuum and a
soft brush. (See Figure 11.)
NOTE : After cleaning, inspect the heat exchangers to
ensure they are free of all foreign objects that may restrict
flow of combustion products.
8. Reverse items 6 through 1 for reassembly.
9. Refer to furnace wiring diagram and reconnect wires
to flame rollout switch, gas valve, igniter, and flame
sensor.
10. Turn on gas and electrical supplies to furnace.
11. Check furnace operation through 2 complete heat
operating cycles. Look at burners. Burner flames