PG92MSA: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
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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  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.
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
Fig. 68.
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
Fig. 71.
A11273
Fig. 71 – Cleaning Heat Exchanger Cell
WARNING
!
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
!
FIRE OR EXPLOSION HAZARD
Failure  to  follow  this  warning  could  result  in  personal  injury,  death,
and/or property damage. 
Never purge  a gas line into a combustion chamber. 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, personal injury
or loss of life.
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.