Venting And Combustion Air Piping - Rheem Gra Series Installation Instructions Manual

4. Connect the furnace to the
supply air plenum.
5. Connect the return air ducting to
the return air opening at the top
of the unit. Make the connection
air tight to prevent entraining
combustion gases from an
adjacent fuel-burning appliance.
6. Be sure to have adequate
space for the unit filter.
NOTE: DO NOT take return air
from bathrooms, kitchens,
furnace rooms, garages, utility or
laundry rooms, or cold areas.
HORIZONTAL UNIT
IMPORTANT: This furnace may only
be installed so as when facing the
front of the furnace, supply air is
discharged on the left hand side.
1. Position the unit to minimize long
runs or runs with many turns and
elbows.
2. If summer air conditioning is
desired, position the indoor coil
on the left end of the unit. Insure
that no air can bypass this coil.
3. Connect the furnace to the
supply air plenum.
4. Connect the return air ducting to
the return air opening at the right

VENTING AND COMBUSTION AIR PIPING

VENTING AND COMBUSTION AIR PIPING
GENERAL INFORMATION
WARNING
!
READ AND FOLLOW ALL
INSTRUCTIONS IN THIS SECTION.
FAILURE TO PROPERLY VENT
THIS FURNACE CAN CAUSE
CARBON MONOXIDE POISONING
OR AN EXPLOSION OR FIRE,
RESULTING IN PROPERTY
DAMAGE, PERSONAL INJURY
OR DEATH.
This furnace removes both sensible
and latent heat from the combustion
flue gases. Removal of latent heat
results in condensation of flue gas
water vapor. This condensed water
vapor drains from the secondary heat
exchanger and out of the unit into a
drain trap.
When installed as a non-direct vent
furnace, only exhaust piping is
required and inside combustion air
may be used. Refer to section on
"COMBUSTION & VENTILATION AIR
FOR FURNACE INSTALLATIONS."
Direct vent installations require a
dedicated combustion air and venting
system. All air for combustion is taken
from the outside atmosphere and all
combustion products are discharged
to the outdoors.
14
14
end of the unit. Make the
connection air tight to prevent
pulling combustion gases from
an adjacent fuel-burning
appliance.
5. Be sure to have adequate
space for the unit filter.
FIGURE 10
COMBUSTIBLE FLOOR BASE
WARNING
!
IN CANADA, ONLY cUL CERTIFIED
PLASTIC VENT PIPE (PVC/CPVC)
CAN BE USED TO VENT GAS FIRE
APPLIANCES. THE VENTING
MATERIAL MUST BE CERTIFIED
FOR COMPLIANCE TO ULC S636.
The combustion air and vent pipe
fittings must conform to American
National Standards Institute (ANSI)
and American Society for Testing
Materials (ASTM) standards as
shown below:
PIPE & FITTING MATERIAL
Schedule 40 PVC (Pipe)
Schedule 40 PVC (Cellular Core Pipe)
Schedule 40 PVC (Fittings)
SDR-21PVC (Pipe)
SDR-26 PVC (Pipe)
Schedule 40 ABS Cellular Core DWV (Pipe)
Schedule 40 ABS (Pipe)
Schedule 40 ABS (Fittings)
ABS-DWV (Drain Waste & Vent)
(Pipe & Fittings)
PVC-DWV (Drain Waste & Vent)
(Pipe & Fittings)
NOTE: DO NOT take return air
from bathrooms, kitchens,
furnace rooms, garages, utility or
laundry rooms, or cold areas.
OVERTEMPERATURE
SAFETY SWITCHES
Furnaces are equipped with safety
switches in the control compartment
to protect against overtemperature
conditions caused by inadequate
combustion air supply. The switches
for the upflow and downflow models
are located in the burner
compartment. If a switch is tripped it
must be manually reset.
ASTM
SPECIFICATION
D1785
F891
D2466
D2241
D2241
F628
D1527
D2468
D2661
D2665