Checklist - Bryant 987MA Installation, Start-Up, Operating And Service And Maintenance Instructions

stricted return- -air supply or motor failure. If limit control
does not function during this test, cause must be determined
and corrected.
a. Run furnace for at least 5 minutes.
b. Gradually block off return air with a piece of cardboard or
sheet metal until the limit trips.
c. Unblock return air to permit normal circulation.
d. Burners will re- -light when furnace cools down.
2. Check Pressure Switch(es)
This control proves operation of the draft inducer blower.
a. Turn off 115- -v power to furnace.
b. Disconnect inducer motor lead wires from wire harness.
c. Turn on 115- -v power to furnace.
d. Set thermostat to "call for heat" and wait 1 minute. When
pressure switch is functioning properly, hot surface igniter
should NOT glow and control diagnostic light flashes a
status code 32. If hot surface igniter glows when inducer
motor is disconnected, shut down furnace immediately.
e. Determine reason pressure switch did not function prop-
erly and correct condition.
f. Turn off 115- -v power to furnace.
g. Reconnect inducer motor wires, replace blower door, and
turn on 115- -v power.
h. Blower will run for 90 seconds before beginning the call
for heat again.
i. Furnace should ignite normally.

Checklist

1. Put away tools and instruments. Clean up debris.
2. Verify that switches SW1- -1 and SW1- -6 are OFF and other
setup switches are set as desired. Verify that switches
SW1- -7 and SW1- -8 for the blower OFF DELAY are set as
desired per Table 17.
3. Verify that blower and control doors are properly installed.
4. Cycle test furnace with room thermostat.
5. Check operation of accessories per manufacturer's instruc-
tions.
6. Review Owner's Manual with owner.
7. Attach literature packet to furnace.
MODULATING
ON/OFF Switch
Turn screw 1 click per
second to adjust rate.
Clockwise to increase
rate, counter clockwise
to decrease rate.
Inlet
Pressure Tap
Min/Max Heat Adust
(Under Cap)
1/2" NPT Outlet
Manifold
Pressure Tap
61
Fig. 50 - - Gas Valve
Fig. 51 - - Orifice Hole
THERMOSTAT SUBBASE
TERMINALS WITH
THERMOSTAT REMOVED
(ANITICIPATOR, CLOCK, ETC.,
MUST BE OUT OF CIRCUIT.)
HOOK-AROUND
AMMETER
R Y W G
10 TURNS
FROM UNIT 24-V
CONTROL TERMINALS
5.0 AMPS ON AMMETER
=
EXAMPLE:
10 TURNS AROUND JAWS
Fig. 52 - - Amp. Draw Check with Ammeter
A10496
BURNER
ORIFICE
A93059
0.5 AMPS FOR THERMOSTAT
ANTICIPATOR SETTING
A96316