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the registers or in the ductwork. Set thermostat fan switch
to "Auto," the blower will shut down in 60 seconds.
Short Cycle Protection — For single phase units only,
with the system operating in cooling mode, note the
temperature setting of the thermostat and gradually raise
the set-point temperature until the unit de-energizes.
Immediately lower the set point temperature of the
thermostat to its original setting and verify that the indoor
blower is energized. Verify that after approximately 5
minutes the compressor and fan energize and that the
temperature of the discharged air is cooler than the room
temperature.
System Cooling
1.
Set the thermostat system switch to "Cool" and the
thermostat fan switch to "Auto." Gradually lower the
thermostat temperature switch below room
temperature and observe that the blower, compressor
and fan energize. Check that air cooler than room
temperature is being discharged at the register.
Listen for any unusual noises. Locate the source
and correct as needed.
2.
After allowing the unit to run for several minutes, set
the temperature selector above room temperature,
verify that:
a. The fan and compressor cycle off with the
thermostat.
b. The blower also stops after the 90 second
delay.
System Heating
1.
Set the thermostat to the lowest setting.
2.
Follow the procedures given on the operating
instruction label, in this installation instructions or
attached inside the louvered control access panel.
3.
Set the thermostat above room temperature and
verify the sequence of operation. (See Operating
Sequence on page 25.)
4.
Verify that the compressor and outdoor fan motor are
not energized.
5.
After the unit has run for approximately five minutes,
set the thermostat below room temperature and
verify the shutdown sequence. (See Operating
Sequence on page 25.)
Verifying and Adjusting Firing Rate — The firing rate
must be verified for each installation to prevent over-firing
of the furnace.
!
CAUTION:
Do not re-drill the burner orifices. If the orifice
size must be changed, use only new orifices.
IMPORTANT NOTE: The firing rate must not exceed the
rate shown on the unit data label. At altitudes above
2,000 ft. it must not exceed that on the data label less
4% for each 1,000 ft.
Follow the procedure below to determine the firing rate:
1.
Shut off all other gas fired appliances.
2
Start the unit in heating mode and allow it to run for
at least three minutes.
3.
Measure the time (in seconds) required for the gas
meter to complete one revolution.
4.
Convert the time per revolution to cubic feet of gas
per hour using Table 8.
5.
Multiply the gas flow rate in cubic feet per hour by the
heating value of the gas in Btu per cubic foot to obtain
the firing rate in Btu per hour. Example:
a. Time for one revolution of a gas meter with a
one cubic foot dial = 40 seconds.
b. From Table 8 read 90 cubic feet per hour of gas.
c. Heating value of the gas (obtained from gas
supplier) = 1040 Btu per cubic foot.
d. Firing rate = 1040 x 90 = 93,600 Btuh.
6.
Adjustments to the firing rate can be made by
adjusting the gas manifold pressure. See the High
Altitude Application section for additional information
of firing rate at elevations above 2000 ft.
The manifold pressure must be set to the appropriate value
for your installation. Refer to either Table 5 for natural gas or
Table 6 for LP/propane gas to verify the manifold pressure
setting required for your particular installation. To adjust the
manifold pressure, remove the regulator cap and turn the
adjusting screw clockwise to increase pressure or counter-
clockwise to reduce pressure. Replace the regulator cap
after adjustments are complete.
Verifying and Adjusting Temperature Rise — Verify that
the temperature rise through the unit is within the range
specified on the unit data label. Temperature rises outside
the specified range could result in premature heat exchanger
failure.
Place thermometers in the return and supply air stream as
close to the duct connections as possible. The thermometer
on the supply air side must be shielded from direct radiation
from the heat exchanger to avoid false readings. Adjust
all registers and duct dampers to the desired position and
run the unit for ten to fifteen minutes before taking any
temperature readings. The temperature rise is the difference
between the supply and return air temperatures.
For typical duct systems, the temperature rise will fall
within the range specified on the data label with the blower
speed at the factory recommended setting (see Table 3).
If the temperature rise measured is outside the range
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