A. GENERAL
These high altitude conversion kits are to be used only
with furnace product lines
*UD-C-K0 and later; *DD-C-F0 and later;
*UD-R-K0 and later; *DD-R-F0 and later;
*UE-A-L0 and later; *DE-A-M0 and later;
CUB-A-C0 and later; CDB-A-D0 and later and used with
natural or LP gas.
These instructions describe the required conversions of
furnaces necessary for installation above an altitude of
4000 feet above sea level.
Due to the lower density of air at higher altitudes, there
would be insufficient negative pressure developed by
the induced draft blower to maintain normal operation.
Therefore, to compensate for the less dense air, pres-
sure switches must be changed to prevent nuisance
lockouts and/or cycling of the reduced draft blower on
high speed. Please note that with the reduced firing in
-
put rates that are required for high altitude installations,
the induced draft blower has ample capacity to provide
sufficient combustion air for proper and safe operation.
Refer to the National Fuel Gas Code, Section 8.1.2 and
Appendix F, for information regarding the correct proce-
dure to derate the furnace’s input. The following instruc-
tions must be followed to convert these furnaces to high
altitude applications.
Installer’s
Guide
s
s
WARNING
!
B. CONVERSION
These instructions apply to models of the
*UD-C-K0 and later; *DD-C-F0 and later;
*UD-R-K0 and later; *DD-R-F0 and later;
*UE-A-L0 and later; *DE-A-M0 and later;
CUB-A-C0 and later; CDB-A-D0 and later product lines.
1. Check for damage to kit contents, and check for all
items listed in the table.
2. Disconnect electrical supply to the furnace, if in-
stalled.
3. Remove the wiring connections from the pressure
switch(es) in the furnace. Mark the wires if needed
to properly identify the replacement.
4. Remove the pressure switch(es) sample tube from
the switch assembly.
5. Remove the pressure switch(es) from the unit.
6. Install the new pressure switch(es) in the same loca-
tion and manner as the old pressure switch(es).
7. Connect the pressure switch sample tube and elec-
trical connections.
8. Reconnect the electrical supply to the unit.
C. CHECKOUT
Adjust input rate, manifold pressure & install correct
main burner gas orifice size according to the unit In
-
staller’s Guide. Once the furnace has been correctly
rated for the high altitude installation, and the pressure
switch has been changed, the furnace installation shall
be checked for proper installation and performance.
Refer to the installer’s guide for checkout procedure. Fill
out the information on the conversion label (part number
A343079P01) and attach the label to the exterior fur-
nace door.
D. NOTES
1. The use of high altitude calibrated pressure switches
in sea level applications is not permitted.
2. The high altitude pressure switches are factory cali-
brated and sealed. Field adjustment is not permitted.
If the factory seal is broken, the product warranty
may be voided.
18-CH25D1-4A-EN
ALL phases of this installation must comply with
NATIONAL, STATE AND LOCAL CODES
Model:
BAYHALT248
BAYHALT249
HIGH ALTITUDE
CONVERSION KITS
IMPORTANT
—This Document is
customer property
and is to remain with this unit. Please return to service infor-
mation pack upon completion of work.
Safety Warning
This conversion kit shall be installed by a qualified
service agency in accordance with the furnace
manufacturer’s instructions and all applicable
codes and requirements of the authority having
jurisdiction. The qualified service agency is
responsible for the proper installation of the
kit. The installation is not proper and complete
until the operation of the converted furnace is
checked as specified in the furnace manufacturer’s
instructions supplied with the kit. Failure to
follow the safetly warning could result in a fire,
an explosion or production of carbon monoxide
causing property damage, personal injury or loss
of life.
CAUTION
Before proceeding with conversion, the gas
supply shall be shut off prior to disconnecting the
electrical power.
