Installation Instructions

ATTENTION INSTALLING PERSONNEL
As a professional installer you have an obligation to know the
product better than the customer. This includes all safety
precautions and related items.
Prior to actual installation, thoroughly familiarize yourself with
this Instruction Manual. Pay special attention to all safety
warnings. Often during installation or repair it is possible to
place yourself in a position which is more hazardous than when
the unit is in operation.
Remember, it is your responsibility to install the product safely
and to know it well enough to be able to instruct a customer in
its safe use. Safety is a matter of common sense...a matter of
thinking before acting. Most dealers have a list of specific good
safety practices...follow them.
The precautions listed in this Installation Manual are intended
as supplemental to existing practices. However, if there is a
direct conflict between existing practices and the content of
this manual, the precautions listed here take precedence.
RECOGNIZE THIS SYMBOL
AS A SAFETY PRECAUTION
DESCRIPTION
This kit contains the appropriate burner orifices, and pres-
sure switch for the application of 90% furnaces in installa-
tions above their maximum (as shipped) rated altitudes. This
kit is not applicable in Canada. Parts apply as shown in the
table below.
Natural Gas
Orifices
Propane Gas
Orifices
Pressure
Switch
B2589907 (#49) B2589908 (#56)
0130F00498
(-.45 / -.85)
Above 7,000 Feet
Table 1
Above an altitude of 7,000 feet, a derating of the appliance
must be followed since the CFM moved by the induced draft
blower remains almost constant while the pounds of oxygen
in that air is reduced as altitude increases. If this procedure
is not followed and the fuel input is not reduced the resulting
combustion can be inefficient, incomplete, or possibly cause
premature heat exchanger failure due to excessive tempera-
ture rise. The burner orifices in the high altitude kits have
been selected as a result of agency certified testing at high
altitude and will provide the appropriate derate. Orifice se-
lection is based on non-derated gas [at standard conditions
of 29.92 in Hg and 60°F—approximately 1,000 Btu/ft
3
for
natural gas and 2,500 Btu/ft
3
for propane]. If the Btu con-
tent of your gas supply has been artificially changed to ac-
count for altitude, contact your gas supplier for orifice siz-
ing (orifice may not require change).
HASFK-2
HIGH ALTITUDE CONVERSION KIT(S)
INSTALLATION INSTRUCTIONS
Do not derate by adjusting the manifold pressure to a lower
pressure setting than specified on the furnace nameplate.
A lower air density in combination with a lower manifold pres-
sure at the burner orifice will prevent the orifice from aspi-
rating the proper amount of air into the burner required for
complete combustion.
In addition to using smaller orifices to reduce the fuel input,
a different pressure switch must be used above the maxi-
mum (as shipped) rated altitude. A high altitude pressure
switch is necessary as a result of the reduction in air density
and is required regardless of the Btu content of the fuel used.
Natural Propane
0 - 7,000 #45 1.25mm
Above 7,000 #49 #56
Altitude (ft.)
Burner Orifice Size
Table 2
CONTENTS
ATTENTION INSTALLING PERSONNEL......................... 1
DESCRIPTION .................................................... 1
IMPORTANT INFORMATION..................................... 2
HASFK-2 .......................................................... 2
Orifice and Pressure Switch Assembly Installation ....... 2
Adjustments and Checks .................................... 3
Manifold Pressure Check .................................... 4
Inspect Burner Flame ........................................ 4
Check and Adjust Unit Temperature Rise ................. 4
IO-833
1/2015