KeepRite F9MAC Series, Service And Technical Support Manual

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SERVICE AND TECHNICAL SUPPORT MANUAL Gas Furnace: (F/G)9MAC
Specifications subject to change without notice.
440 04 4201 03 5
3. Pour one quart (liter) of water into funnel/tube. Water
should run through collector box, overfill condensate
trap, and flow into open field drain.
4. Remove funnel; replace collector box drain plug.
5. Connect field-supplied 5/8-in. (16 mm) ID tube to middle
collector box drain port.
6. Pour one quart (liter) of water into funnel/tube. Water
should run through collector box, overfill condensate
trap, and flow into open field drain.
7. Remove funnel and tube from collector box and replace
collector box drain plug.
Figure 1 Priming Condensate Drain
L11F065
Representative drawing only, some models may vary in appearance.
Purge Gas Lines
If not previously done, purge the lines after all connections
have been made and check for leaks.
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
Adjustments
FURNACE DAMAGE HAZARD
Failure to follow this caution could result in reduced
furnace life.
DO NOT push or force gas valve adjusting screw. This
can result in damage to the adjustment screw resulting in
incorrect manifold pressure, which can result in a no heat
situation or shorten the life of the heat exchangers.
CAUTION
!
Figure 2 Orifice Hole
A93059
BURNER
ORIFICE
For proper operation and long term reliability, the Furnace input
rate must be / − 2 percent of input rate on furnace rating
plate, or as adjusted for altitude.
The gas input rate on rating plate is for installations at altitudes
up to 2000 ft. (610 M).
NOTICE
The NATURAL GAS manifold pressure adjustments in Table 4
and Table 5 compensate for BOTH altitude AND gas heating
value. DO NOT apply an additional de − rate factor to the
pressures shown in Table 4 or Table 5 . The values in these
Tables are NOT referenced to sea level; they are
AS − MEASURED AT ALTITUDE.
The heating content of natural gas at altitude may already
provide for a reduction in capacity or the furnace. Be sure to
obtain the expected in − season gas heating value of the gas
from the gas supplier BEFORE making any adjustments for
capacity or altitude. Refer to Table 4 or Table 5 . No
adjustments to the furnace may be necessary at altitude for
certain gas heating values.
Refer to the instructions provided in the factory-specified
LP/Propane conversion kit for instructions for setting gas
manifold pressures for LP/Propane applications.
In the USA , the input rating for altitudes above 2000 ft. (610 M)
must be reduced by 2 percent for each 1000 ft. (305 M) above
sea level. Refer to Table 1 . The natural gas manifold pressures
in Table 4 and Table 5 adjust for BOTH altitude and natural gas
heating value.
In Canada , the input rating must be reduced by 5 percent for
altitudes of 2000 ft. (610 M) to 4500 ft. (1372 M) above sea
level. The natural gas manifold pressures in Table 4 and
Table 5 adjust for BOTH altitude and natural gas heating value.
NOTE : For Canadian altitudes of 200 to 4500 ft. (610 to 1372
M), use USA altitudes of 2001 to 3000 ft. (611 to 914 M) in
Table 4 and Table 5 .
To adjust manifold pressure to obtain the proper input rate, first,
determine if the furnace has the correct orifice installed. At
higher altitudes or different gas heat contents, it may be
necessary to change the factory orifice to a different orifice.
Tables have been provided in the furnace Service and
Technical Manual to match the required orifice to the manifold
pressure to the heat content and specific gravity of the gas.
NOTE : There are two sets of manifold pressure tables. Use
Table 4 for all models EXCEPT *9MAC0602120 Btuh model.
Use Table 5 for only the *9MAC0602120 model.