Check Safety Controls; Checklist - Bryant 830SA Installation, Start-Up, Operating And Service And Maintenance Instructions

WARNING
!
FIRE HAZARD
Failure to follow this warning could result in personal
injury, death, and/or property damage.
Gas valve outlet pressure tap must be tightened to prevent
gas leak.
CAUTION
!
FURNACE OVERHEATING HAZARD
Failure to follow this caution may result in reduced furnace
life.
Recheck temperature rise. It must be within limits specified
on the rating plate. Recommended operation is at the
mid- -point of rise range or slightly above.
7. Set thermostat heat anticipator.
a. Mechanical thermostat - - Set thermostat heat anticipator
to match the amp. draw of the electrical components in
the R- -W circuit. Accurate amp. draw readings can be ob-
tained at the wires normally connected to thermostat sub-
base terminals, R and W. The thermostat anticipator
should NOT be in the circuit while measuring current.
(1.) Remove thermostat from subbase or from wall.
(2.) Connect an amp. meter as shown in Fig. 34 across
the R and W subbase terminals or R and W wires at
wall.
(3.) Record amp. draw across terminals when furnace is
in heating and after blower starts.
(4.) Set heat anticipator on thermostat per thermostat in-
structions and install on subbase or wall.
b. Electronic thermostat: Set cycle rate for 4 cycles per hr.
8. Adjust blower off delay. The blower off delay has four (4)
adjustable settings from 90 seconds to 180 seconds. The
blower off delay jumpers are located on the furnace
control board. (See wiring diagram Fig. 38) Position A- -90
seconds, B- -120 seconds, C- -150 seconds, D- -180 seconds.
To change the blower off delay setting, move the jumper
from one set of pins on the control to the pins used for the
selected blower off delay. Factory off delay setting is 120
seconds.
9. Cooling On Delay is fixed at 2 seconds for either jumper
selection.

Check Safety Controls

1. Check Main Limit Switch(es)
This control shuts off combustion control system and en-
ergizes air- -circulating blower motor, if furnace overheats.
By using this method to check limit control, it can be es-
tablished that limit is functioning properly and will operate
if there is a restricted duct system 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.
10 TURNS
EXAMPLE: 5.0 AMPS ON AMMETER
10 TURNS AROUND JAWS
Fig. 34 - - Amp. Draw Check With Ammeter
2. Check draft safeguard switch.
The purpose of this control is to cause the safe shutdown
of the furnace during certain blocked vent conditions.
a. Verify vent pipe is cool to the touch.
b. Disconnect power to furnace and remove vent connec-
tor from furnace vent elbow.
c. Restore power to furnace and set room thermostat
above room temperature.
d. After normal start- -up, allow furnace to operate for 2
minutes, then block vent elbow in furnace 80 percent
of vent area with a piece of flat sheet metal.
e. Furnace should cycle off within 2 minutes. If gas does
not shut off within 2 minutes, determine reason draft
safeguard switch did not function properly and correct
condition.
f. Remove blockage from furnace vent elbow.
g. Switch will auto- -reset when it cools.
h. Re- -install vent connector.

Checklist

1. Put away tools and instruments. Clean up debris.
2. Verify blower off delay are set as desired. (See wiring
diagram Fig. 38) Position A- -90 seconds, B- -120 seconds,
C- -150 seconds, D- -180 seconds. Factory off delay setting
is 120 seconds.
3. Cooling On Delay is fixed at 2 seconds for either jumper
selection.
4. Verify that blower and burner access doors are properly
installed.
5. Cycle test furnace with room thermostat.
6. Check operation of accessories per manufacturer's
instructions.
7. Review User's Guide with owner.
8. Attach literature packet to furnace.
26
THERMOSTAT SUBBASE
TERMINALS WITH
THERMOSTAT REMOVED
(ANITICIPATOR, CLOCK, ETC.,
MUST BE OUT OF CIRCUIT.)
HOOK-AROUND
AMMETER
R Y W G
FROM UNIT 24-V
CONTROL TERMINALS
= 0.5 AMPS FOR THERMOSTAT
ANTICIPATOR SETTING