PG96MSA: 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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All  fuel-burning  equipment  must  be  supplied  with  air  for  fuel
combustion. Sufficient air must be provided to avoid negative pressure
in the equipment room or space. A positive seal must be made between
the furnace cabinet and the return-air duct to prevent pulling air from the
burner area.
AIR FOR COMBUSTION AND VENTILATION 
Introduction
Direct Vent (2-pipe) Applications
When the furnace is installed as a 2-pipe furnace, no special provisions
for  air  for  combustion  are  required.  However,  other  gas  appliances
installed  in  the  space  with  the  furnace  may  require  outside  air  for
combustion.  Follow  the  guidelines  below  to  ensure  that  other  gas
appliances have sufficient air for combustion.
Direct Vent (1-pipe) Applications
When the furnace is installed as a 1-pipe furnace, it will be necessary to
ensure  there  is  adequate  air  for  combustion.  Other  gas  appliances
installed  with  the  furnace  may  also  require  air  for  combustion  and
ventilation in addition to the amount of combustion air  and ventilation
air required for the furnace. Follow the guidelines below to ensure that
the furnace and other gas appliances have sufficient air for combustion.
Ventilated Combustion Air Applications (for U.S. Only)
When the furnace is installed using the ventilated combustion air option,
the  attic  or  crawlspace  must  freely  communicate  with  the  outdoor  to
provide sufficient air for combustion. The combustion air pipe cannot be
terminated in attics or crawlspaces that use ventilation fans designed to
operate during the heating season. If ventilation fans are present in these
areas,  the  combustion  air  pipe  must  terminate  outdoors  as  a  2-Pipe
system.
All air for combustion is piped directly to the furnace from a space that is
well  ventilated  with  outdoor  air  (such  as  an  attic,  crawl  space  or
equipment closet) and the space is well isolated from the living space or
garage. In addition, other gas appliances installed in the space with the
furnace may require  outside air for combustion.  Follow the guidelines
below  to  ensure  that  the  roof  or  crawlspace  walls  have  sufficient  free
area  to  provide  sufficient  air  for  combustion  and  ventilation  for  the
furnaces.  The  guidelines  below  can  be  used  to  ensure  that  other  gas
appliances have sufficient air for combustion.
Provisions for adequate combustion, ventilation, and dilution air must be
provided in accordance with:
• U.S.A.  Installations:  Current  edition  of  Section  9.3  of  the  NFPA
54/ANSI Z223.1, Air for Combustion and Ventilation and applicable
provisions of the local building codes.
CAUTION
!
PERSONAL INJURY AND/OR PROPERTY DAMAGE 
HAZARD
Improper  use  or  installation  of  this  furnace  may  result  in  premature
furnace  component  failure.  Unless  otherwise  prohibited,  this  gas
furnace may be used for heating buildings under construction provided
that:
- The furnace is permanently installed with all electrical wiring, 
piping, venting and ducting installed according to these 
installation instructions. A return air duct is provided, sealed to 
the furnace casing, and terminated outside the space containing 
the furnace. This prevents a negative pressure condition as 
created by the circulating air blower, causing a flame rollout 
and/or drawing combustion products into the structure. 
- The furnace is controlled by a thermostat. It may not be “hot 
wired” to provide heat continuously to the structure without 
thermostatic control. 
- Clean outside air is provided for combustion. This is to 
minimize the corrosive effects of adhesives, sealers and other 
construction materials. It also prevents the entrainment of 
drywall dust into combustion air, which can cause fouling and 
plugging of furnace components. 
- The temperature of the return air to the furnace is maintained 
between 55°F (13°C) and 80°F (27°C), with no evening setback 
or shutdown. The use of the furnace while the structure is under 
construction is deemed to be intermittent operation per our 
installation instructions. 
- The air temperature rise is within the rated rise range on the 
furnace rating plate, and the gas input rate has been set to the 
nameplate value. 
- The filters used to clean the circulating air during the 
construction process must be either changed or thoroughly 
cleaned prior to occupancy. 
- The furnace, ductwork and filters are cleaned as necessary to 
remove drywall dust and construction debris from all HVAC 
system components after construction is completed. 
- Verify proper furnace operating conditions including ignition, 
gas input rate, air temperature rise, and venting according to 
these installation instructions.
WARNING
!
CARBON MONOXIDE POISONING / COMPONENT 
DAMAGE HAZARD
Failure to follow this warning could result in personal injury or death
and unit component damage. 
Corrosive or contaminated air may cause failure of parts containing flue
gas, which could leak into the living space. Air for combustion must not
be  contaminated  by  halogen  compounds,  which  include  fluoride,
chloride,  bromide,  and  iodide.  These  elements  can  corrode  heat
exchangers  and  shorten  furnace  life.  Air  contaminants  are  found  in
aerosol  sprays,  detergents,  bleaches,  cleaning  solvents,  salts,  air
fresheners, and other household  products.  Do  not  install  furnace  in  a
corrosive or contaminated atmosphere. Make sure all combustion and
circulating air requirements are met, in addition to all local codes and
ordinances.