Start-Up, Adjustment, And Safety Check - Bryant 987MB Installation, Start-Up, Operating And Service And Maintenance Instructions

987MB: Installation, Start-up, Operating and Service and Maintenance Instructions
START-UP, ADJUSTMENT, AND SAFETY
CHECK
!
Important Installation and Start-up Procedures
Failure to follow this procedure may result in a nuisance smoke or odor
complaint.
The manifold pressure, gas rate by meter clocking, temperature rise and
operation must be checked after installation. Minor smoke and odor
may be present temporarily after start-up from the manufacturing
process. Some occupants are more sensitive to this minor smoke and
odor. It is recommended that doors and windows be open during the
first heat cycle.
General
1. Furnace must have a 115-v power supply properly connected and
grounded.
NOTE: Proper polarity must be maintained for 115-v wiring. Control
status indicator light flashes rapidly and furnace does not operate if
polarity is incorrect or if furnace is not grounded.
2. Thermostat wire connections at terminals R, W/W1, G, and Y/Y2
must be made at 24-v terminal block on furnace control. See
communicating wall control instructions for proper wiring of
communicating controls.
3. Natural gas service pressure must not exceed 0.5 psig (14- in. w.c.,
350 Pa), but must be no less than 0.16 psig (4.5-in. w.c., 1125 Pa).
4. Blower door must be in place to complete 115-v electrical circuit
and supply power to the furnace components.
CAUTION
!
UNIT OPERATION HAZARD
Failure to follow this caution may result in intermittent unit operation
or performance dissatisfaction.
These furnaces are equipped with a manual reset limit switch in burner
assembly. This switch opens and shuts off power to the gas valve if an
overheat condition (flame
assembly/enclosure. Correct
improper gas pressure setting, improper burner or gas orifice
positioning, or improper venting condition before resetting switch. DO
NOT jumper this switch.
Before operating furnace, check flame rollout manual reset switch for
continuity. If necessary, press button to reset switch.
EAC-1 terminal is energized whenever blower operates, HUM terminal
is only energized when blower is energized in heating.
Setup Switches
There are four (4) sets of setup switches on the furnace control board.
These switches configure the furnace for correct application
requirement. They also select the airflow settings for Air Conditioning
and Continuous Fan airflows.
The Setup Switch locations are shown and described on
setup switches are also shown on the unit wiring label.
Setup Switches (SW1)
The furnace control has eight (8) setup switches that may be set to meet
the application requirements. Refer to
section for setup switch configurations. To set these setup switches for
the appropriate requirement:
1. Remove blower door.
2. Locate setup switches on furnace control.
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
NOTICE
rollout) occurs in the
inadequate combustion-air
Fig.
Fig. 60 and the Adjustments
3. Configure the set-up switches as necessary for the application.
4. Replace blower door.
NOTE: If a bypass humidifier is used, setup switch SW1-3 (Min/Int
Heat Rise Adjust) should be in ON position. This compensates for the
increased temperature in return air resulting from bypass.
NOTE: If modulating dampers are used, blower motor automatically
compensates for modulating dampers.
Air Conditioning (A/C) Setup Switches (SW2)
The air conditioning setup switches are used to match furnace airflow to
required cooling airflow or high stage cooling airflow when a two-stage
outdoor unit is used. Refer to
setup switch configurations.
To set the desired cooling airflow:
1. Remove blower door.
2. Locate A/C setup switches on furnace control.
3. Determine air conditioning tonnage used.
4. Configure the switches for the required cooling airflow.
NOTE: Incorrect airflow caused by improper A/C switch setup may
cause condensate blow-off or a frozen indoor coil in the cooling mode.
5. Replace blower door.
Continuous Fan (CF) Setup Switches (SW3)
The Continuous Fan airflow selection via Setup switches SW3 is also the
switch setting for low-speed cooling when the furnace is used with a
two-speed cooling or heat pump unit. Refer to
Adjustments section for setup switch configurations. This setup feature
allows continuous fan airflow or low-cooling airflow to be adjusted. To
set desired continuous fan airflow or low-cooling airflow:
1. Remove blower door.
2. Locate CF setup switches on furnace control.
3. Determine desired continuous fan airflow or low-cooling airflow.
4. Configure the switches for the required continuous fan or
low-cooling airflow.
5. Replace blower door.
Additional Setup Switches (SW4)
The furnace control has three (3) additional setup switches labeled SW4.
Setup switch SW4-2 can be used to lock the furnace into intermediate
burner
heat. When setup switch SW4-2 is ON it will over ride setup switch
supply,
SW1-2 if it is ON. SW4-3 is used to adjust airflow. Refer to
the Adjustments section for setup switch configurations. To activate
setup switch SW4-2 and SW4-3:
1. Remove blower door.
2. Locate setup switch SW4 on furnace control.
3. Configure the switches for the required heat stages and airflow if
necessary.
4. Replace blower door.
60. The
51
Fig. 60 and the Adjustments section for
Table 5
Fig. 60
and the
and