Check Safety Controls; Checklist - Carrier weathermaker 8000 Installation, Start-Up And Operator's Manual

taken after the blower motor has started. See the thermostat
manufacturer's instructions for adjusting the heat anticipator
and for varying the heating cycle length.
NOTE: When using an electronic thermostat, set the cycle rate for
3 cycles per hr.
THERMOSTAT SUBBASE
TERMINALS WITH
THERMOSTAT REMOVED
R Y W G
10 TURNS
FROM UNIT 24-VOLT
TERMINAL BLOCK
5.0 AMPS ON AMMETER
EXAMPLE:
10 TURNS AROUND JAWS
Fig. 14—Amp Draw Check With Ammeter
CHECK SAFETY CONTROLS — The flame sensor, gas valve,
and pressure switch were all checked in the Start-Up Procedures
section as part of normal operation.
1. Check primary limit control.
This control shuts off the combustion control system and
energizes the circulating-air blower motor if the furnace
overheats.
The preferred method of checking the limit control is to
gradually block off the return air after the furnace has been
operating for a period of at least 5 minutes. As soon as the
limit has shut off the burners, the return-air opening should be
unblocked. By using this method to check the limit control, it
can be established that the limit is functioning properly and
operates if there is a motor failure.
Copyright 1996 CARRIER Corp. • 7310 W. Morris St. • Indianapolis, IN 46231
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book 1 4
PC 101 Catalog No. 565-980
Tab 6a 8a
HOOK-AROUND
VOLT/AMMETER
= 0.5 AMPS FOR THERMOSTAT SETTING
A80201
Printed in U.S.A.
2. Check draft safeguard switch.
The purpose of this control is to permit the safe shutdown of
the furnace during certain blocked vent conditions.
a. Disconnect power to furnace and remove vent connector
from furnace outlet collar. Be sure to allow time for vent
pipe to cool down before removing.
b. Restore power to furnace and set room thermostat above
room temperature.
c. After normal start-up, allow furnace to operate for 2
minutes, then block flue outlet 100 percent. Furnace should
cycle off within 2 minutes.
d. Remove blockage and reconnect vent pipe to furnace outlet
collar.
e. Wait 5 minutes and then reset draft safeguard switch.
3. Check pressure switch.
This control proves operation of draft inducer blower.
a. Turn off 115-v power to furnace.
b. Remove control door and 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 ignitor
should NOT glow and control center diagnostic light
flashes a 31 fault. If hot surface ignitor glows when inducer
motor is disconnected, shut down furnace immediately.
Determine reason pressure switch did not function properly
and correct condition.
e. Turn off 115-v power to furnace.
f. Reconnect inducer motor wires, replace control door, and
turn on 115-v power.

CHECKLIST

1. Put away tools, instruments, and clean up debris.
2. Verify manual reset switches have continuity.
3. Ensure blower and control access doors are properly installed.
4. Cycle test furnace with room thermostat.
5. Check operation of accessories per manufacturer's instruc-
tions.
6. Review User's Manual with owner.
7. Leave literature packet near furnace.
Form 58WAV-7SI Pg 16
58wav7si
5-96 Replaces: 58WAV-6SI