KeepRite F96VTN, Installation, Start-Up, Operating And Service And Maintenance Instructions

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F96VTN and G96VTN: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
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measurements, due to possible changes in duct static pressure and
airflow.
When setup switch SW1-4 is ON, operation will be near the high end of
the rise range for improved comfort.
Determine air temperature rise as follows:
1. Place thermometers in return and supply ducts as near furnace as
possible. Be sure thermometers do not see heat exchanger so that
radiant heat does not affect readings. This practice is particularly
important with straight-run ducts.
2. When thermometer readings stabilize, subtract return-air
temperature from supply-air temperature to determine air
temperature rise.
NOTE: Temperature rise can be determined for low-heat and high-heat
operation by locking the furnace in each mode of operation. The mode of
operation is based on the position of Setup Switch SW1-2 on the furnace
control board.
3. This furnace is capable of automatically providing proper airflow to
maintain the temperature rise within the range specified on furnace
rating plate. If temperature rise is outside this range, proceed as
follows:
a. Check gas input for low- and high-heat operation.
b. Check derate for altitude, if applicable.
c. Check all return and supply ducts for excessive restrictions
causing static pressure greater than 0.5-In. W.C.
d. Ensure Comfort/Efficiency SW1-4 on furnace control is in
OFF=Efficiency position when a bypass humidifier is used. See
Fig. 38 for switch location.
e. Verify correct model plug is installed.
To lock the furnace in low heat:
1. Turn SW1-2 ON at the furnace control.
2. Connect a jumper across R and W/W1 at the thermostat terminals at
the furnace control.
3. Allow the burners to ignite and the blower to turn on.
4. Allow the supply temperature to stabilize and verify the proper rise
range.
If the temperature rise is too high or too low in low heat:
1. Remove jumpers from R and W/W1.
2. Wait until the blower off delay is completed.
3. Turn 115 VAC power off.
4. Check the position of setup switch SW1-4. When set to OFF,
airflow is raised 7% for low heat Factory default position is ON.
5. Turn 115 VAC power on.
6. Re-check low heat temperature rise.
To lock the furnace in high heat:
1. Connect a jumper across R and W/W1 and W2 at the thermostat
terminals at the furnace control.
2. Allow the burners to ignite and the blower to turn on.
3. Allow the supply temperature to stabilize and verify the proper rise
range.
If the temperature rise is too high or too low in high heat:
1. Remove jumpers from R and W/W1 and W2.
2. Wait until the blower off delay is completed.
3. Turn 115 VAC power off.
4. Check the position of setup switch SW1-4. When set to OFF,
airflow is raised 7% for low Heat, and 10% for high heat. Factory
default position is ON.
5. Turn 115 VAC power on.
6. Re-check high heat temperature rise.
After the temperature rise has been verified:
1. Remove jumpers from thermostat terminals.
2. Allow the blower off delay to complete.
3. Turn setup switches SW1-2 to the OFF position unless two-stage
thermostat operation is desired. See Fig. 59 .
4. Proceed to “Adjust Blower Off Delay” or install blower door if
complete.
Adjust Blower Off Delay (Heat Mode)
1. Remove blower door if installed.
2. Turn Dip switch SW-7 or SW-8 ON or OFF for desired blower off
delay. See Table 19 and Fig. 38 , Fig. 59 and Fig. 73 .
Table 19 – Blower Off Delay Setup Switch
Adjust Cooling Airflow – High-Speed and
Low-Speed Cooling
The ECM blower can be adjusted for a range of airflows for low-speed
or high-speed cooling. See Table 9 – Air Delivery – CFM (With Filter)
and Fig. 59 – Furnace Setup Switches and Descriptions. Depending on
the model size, the cooling airflow can be adjusted from 1.5 to 6 tons
based on 350 CFM per ton.
NOTE: 6 ton airflow will truncate at 2200 CFM on applicable models.
The high-speed or single-speed cooling airflow is adjusted by turning
Setup switches SW2-6, SW2-7 and SW2-8 either ON or OFF. Select the
required airflow from Table 9 . Table 9 is based upon 350 CFM per ton.
For other CFM per ton Setup switch selections, see Fig. 38 , Fig. 59 and
Fig. 73 .
The Continuous Fan airflow selection via Setup switches SW2 is also the
airflow for low-speed cooling when the furnace is used with a 2-speed
cooling or heat pump unit. Adjust SW2-3, 4, 5 to match the airflow
required for low-speed cooling. Select the required airflow from Table 9
and Fig. 59 .
NOTE: The airflow selected via SW2-3, 4, 5 (Low-Speed Cooling
Airflow) cannot exceed the airflow selected via SW2-6, 7, 8
(High-Speed Cooling Airflow). For other CFM per ton Setup switch
selections, see Fig. 38 and Fig. 59 .
NOTE: The airflow settings for SW2-6, 7, 8 and SW2-3, 4, 5 selections
are the same, EXCEPT for the default values. See Table 9 .
For a complete explanation of cooling airflow, refer to the section titled
“Sequence of Operation.”
CAUTION
!
FURNACE DAMAGE HAZARD
Failure to follow this caution may result in:
S
Overheating the heat exchangers or condensing flue gases in heat
exchanger areas not designed for condensate.
S
Shortened furnace life
S
Component damage.
Temperature rise must be within limits specified on furnace rating plate.
Recommended operation is at midpoint of rise range or slightly above.
DESIRED HEATING MODE
BLOWER OFF DELAY (SEC.)
SETUP SWITCH
(SW1-7 AND -8)
POSITION
SW1-7 SW1-8
90 OFF OFF
120 ON OFF
150 OFF ON
180 ON ON