Check Safety Controls; Check Primary Limit Control; Check Pressure Switch; Checklist - Carrier Series 100 Installation, Start-Up, And Operating Instructions Manual

Table 17—Speed Selector
COLOR
Black
Yellow (When Present)
Blue
Red
White
Table 18—Blower Off Delay Jumper Positions
PINS 1 AND 2
Time (in sec) 90
be disconnected from R and W wires during current measurement.
See thermostat manufacturer's instructions for adjusting heat
anticipator and for varying heating cycle length.
For an electronic thermostat, set cycle rate for 3 cycles per hour.
Step 6—Check Safety Controls
This section covers the safety controls that must be checked before
the installation is complete. The flame sensor, gas valve, and
pressure switch were all checked in the Start-up procedure section
as part of normal operation.

CHECK PRIMARY LIMIT CONTROL

This control shuts off gas control system and energizes air-
circulating blower motor if furnace overheats. Recommended
method of checking this limit control is to gradually block off
return air after furnace has been operating for a period of at least
5 minutes. As soon as limit control has shut off burners, return-air
opening should be unblocked to permit normal air circulation. By
using this method to check limit control, it can be established that
limit is functioning properly and operates if there is a restricted
return-air duct or motor failure. If limit control does not function
during this test, cause must be determined and corrected.

CHECK PRESSURE SWITCH

This control proves operation of draft inducer. Check switch
operation as follows:
1. Turn off 115-v power to furnace.
2. Remove outer furnace door and disconnect inducer motor
from wire harness.
3. Turn on 115-v power to furnace.
4. Set thermostat to "call for heat" and wait 1 minute. When
pressure switch is functioning properly, hot surface igniter
should NOT glow, and control status code LED flashes a
Status Code 31. If hot surface igniter glows when inducer
motor is disconnected, shut furnace down immediately. De-
termine reason pressure switch did not function properly and
correct condition.
5. Turn off 115-v power to furnace.
6. Reconnect inducer motor leads, reinstall main furnace door,
and turn on 115-v power supply.
FACTORY-
SPEED SHIPPED
CONNECTION
High Cool
Medium High Spare
Medium Low Heat
Low Fan
Common C
OM
2 AND 3 3 AND 4 4 AND 5
120 150 180
THERMOSTAT SUBBASE
TERMINALS WITH
THERMOSTAT REMOVED
10 TURNS
EXAMPLE: 5.0 AMPS ON AMMETER
10 TURNS AROUND JAWS
Fig. 58—Amp Draw Check with Ammeter
Step 7—Checklist
1. Put away tools and instruments. Clean up debris.
2. Verify flame-rollout manual reset switch has continuity.
3. Verify that blower and main outer 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 Guide with owner.
7. Leave literature packet near furnace.
56
HOOK-AROUND
VOLT/AMMETER
R Y W G
FROM UNIT 24-VOLT
TERMINAL BLOCK
= 0.5 AMPS FOR THERMOSTAT SETTING
A80201