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Table18--BlowerOff DelaySetupPosition
PiNS
1 AND 2
2 AND 3
3 AND 4
4 AND 8
Time (in sec)
90
120
150
180
delay setting,
move
the jumper
flora one set of pins on the conhol
board
to the pins used
for the desired
blower
off delay.
Factoiw
blower
off delay
setting is 120 sec.
SET THERMOSTAT
HEAT
ANTI(IPATOR
When
using
a nonelectronic
them_ostat,
the
them_ostat
heat
anticipator
must be set to match
amp draw of components
in R-W
circuit.
Accurate
amp
draw
measurements
can be
obtained
at
thermostat
subbase
terminals
R and W. Fig. 49 illustrates
an easy
method
of obtaining
these measurements.
The anap reading
should
be taken
after blower
motor
has
started
and furnace
is heating.
Connect
ammeter
wires
as shown
in Fig.
49.
The thermostat
anticipator
should NOT be in the circuit
while measuring
current.
If them_ostat
has no subbase,
the them?ostat
must be disconnected
from R and W wires during
cun'ent measurement.
See thermostat
manufacturer's
instructions
for adjusting
heat anticipator
and for
raving
heating
cycle tengd_.
For an electronic
thermostat,
set cycle rate for 3 cycles
per hour.
CHECK
SAFETY
CONTROLS
This section covers
the safety controls
that must be checked
be_bre
the installation
is complete.
The
flame
sensor,
gas
valve,
and
pressure
switch
were all checked
in the Start=up procedure
section
as part of nom_al
operation.
Step
l--Check
Primary
Limit
Control
This
control
shuts
off
gas
control
system
and
energizes
air-
circulating
blower
motor
it" fm'nace
overheats
Recommended
method
of checking
this
limit
control
is to gradually
block
off
return
air aker
furnace
has been operating
for a period
of at least
5 minutes.
As soon as limit control
has shut offburners,
return-air
opening
should
be unblocked
to pem_it nora?HI air circulation.
By
using
this method
to check
limit control,
it can be established
that
limit is t\mctioning
properly
and operates
if there
is a restricted
return-air
duct or motor
_i_ilure. If limit control
does not [hnction
during
this test, cause
must be determined
and con'ected.
Step
2--Check
Pressure
Switch
This
control
pIoves
opeiation
of draf_ inducer
(heel<
switch
operation
as fbllows:
1. Turn off 115-v power
to furnace.
TERMINALS
WITH
THERMOSTAT
REMOVED
2
Remove
main fi/rnace
door and disconnect
inducer
motor lead
wires flora wire harness.
3. Turn on 115-v power
to furnace.
4
Set them_ostat
to "call
for heat"
and wait
1 minute
When
pressure
switch
is _imctioning
properly,
hot surface
igniter
should NOT glow, and control
status code LED flashes
status
code 31 _imlt. [f hot sur_itce igniter g!ows when inducer
motor
is disconnected,
shut furnace
down
immediately.
Determine
reason
pressure
switch
did not function
properly
and correct
condition.
5. Turn off 115=v power
to _i/rnace.
6. Reconnect
inducer
motor
leads,
reinstall
main
furnace
door,
and mm on 115=v power
supply.
CHECKUST
1
Put away tools and instruments.
(lean
up debris.
2
Verify
flame rollout
manual
reset switch
has continuity.
3. Verify
that
blower
and
main
access
doors
are
properly
installed.
4. Cycle
test fi_rnace with room them_ostat.
5. Check
operation
of accessories
per
manufacturer's
instl_ac-
lions.
6
Review
User's
Guide with
owner
7. Leave
literature
packet
near furnace.
FROM UNIT 24-VOLT
TERMINAL
BLOCK
EXAMPLE:
5 0 AMPS
ON AMMETER
= 0.5 AMPS
FOR
THERMOSTAT
SETTING
10 TURNS
AROUND
JAWS
A80201
Fig. 49--Amp
Draw Check w{th Ammeter
45
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