60
(Read following caution before changing taps).
UNIT DAMAGE HAZARD
To avoid operating outside the rise range and avoid
component damage:
1. NEVER connect Speed Tap 1 (Red) wire to “HI HT.”
2. NEVER connect Speed Tap 2 (Orange) wire to “HI HT”
on all models.
CAUTION
!
To change blower motor speed selections for heating mode,
remove blower motor lead from control HI-HT terminal. (See
Fig. 37.) Select desired blower motor speed lead from one of the
other motor leads and relocate it to HI-HT terminal. (See Table
18 for lead color identification.) Reconnect original lead on
SPARE terminal. Follow this same procedure for proper selection
of LO-HT and COOL speed selection.
Set Blower Off Delay
a. Remove Blower Access Door if installed.
b. Turn Dip switch 2 and 3 ON or OFF for desired
blower off delay. See Tables 11 and 12 or Fig. 36
and 37.
ADJUST BLOWER OFF DELAY (HEAT MODE)
If desired, the main blower off time delay period may be
lengthened or shortened when operating in the heating mode to
provide greater comfort. See Table 11 for position of switches
and Fig. 36 or 37 for location of switches on control center.
SET THERMOSTAT HEAT ANTICIPATOR
When using a nonelectronic thermostat, the thermostat
heat-anticipator must be set to match the amp draw of
the electrical components in R-W/W1 circuit. Accurate amp
draw readings can be obtained at thermostat subbase terminals
R and W.
Fig. 61 illustrates an easy method of obtaining actual amp draw.
The amp reading should be taken after blower motor has started
and furnace is operating in low heat. To operate furnace in
low-heat, first move SW-1 to ON position, then connect ammeter
wires as shown in Fig. 61. The thermostat anticipator should
NOT be in the circuit while measuring current. If thermostat has
no subbase, the thermostat must be disconnected from R and
W/W1 wires during current measurement Return SW-1 to final
desired location after completing the reading.
See thermostat manufacturer’s instructions for adjusting heat
anticipator and for varying heating cycle length.
When using 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.
1. 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 supply or motor failure. If
limit control does not function during this test, cause must
be determined and corrected.
R
Y W G
1
0
TURNS
THERMOSTAT SUBBASE
TERMINALS WITH
THERMOSTAT REMOVED
HOOK-AROUND
VOLT/AMMETER
EXAMPLE:
5.
0
AMPS ON AMMETER
1
0
TURNS AROUND JAWS
=
0
.5 AMPS FOR THERMOSTAT SETTING
FROM UNIT 24-VOLT
TERMINAL BLOCK
A80201
Fig. 61 -- Amp Draw Check with Ammeter
2. Check Pressure Switch
This control proves operation of draft inducer. Check switch
operation as follows:
a. Turn off 115-v power to furnace.
b. Remove outer furnace 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 igniter should not glow, and status code LED
flashes a Status Code 32. If hot surface igniter glows
when inducer motor is disconnected, shut furnace
down immediately. Determine reason pressure switch
did not function properly and correct condition.
e. Turn off 115-v power to furnace.
f. Reconnect inducer motor leads, reinstall main furnace
door, and turn on 115-v power supply.
CHECKLIST
1. Put away tools and instruments. Clean up debris.
2. Check SW-1 through SW-3 after completing installation to
ensure desired settings for thermostat type (SW-1) and
blower-OFF delay (SW-2 and SW-3).
3. Verify flame rollout manual reset switch has continuity.
4. Verify that blower and outer 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. Leave literature packet near furnace.
