Advertisement
Step 3 -- Supply
Air Adjustment
Check
FIRE
HAZARD
AND UNIT RELIABILITY
Failure
to follow
this warning
could
result
in personal
injury, death and/or property
damage.
When
operating
furnace
in heating
mode.
static pressure
and
temperature
rise
(supply-air
temperature
minus
return-air
temperature)
must be within those limits specified
on rating label.
This
furnace
is equipped
with
a 4-speed
direct-drive
motor
to
deliver
a temperature
rise within
range
specified
on rating
plate,
between
return and supply plenums,
at external
duct static pressure
noted on rating plate.
The supply air must be adjusted
based on heating
/ air conditioning
output
and the stable pressure
of the duct system.
For the desired
air flow,
refer to
Table 5 as well as the air flow tables
based on
static pressure
in Table 6.
Table 5 - Speed
Selection
FURNACE
APPLICATION
HEATING
A/C
HEATING INPUT
OR A/C OUTPUT
0.50 USGPH
0.60 USGPH
0.70 USGPH
2.0 Tons
2.5 Tons
3.0 Tons
RECOMMENDED
BLOWER SPEED
Med - Low
Med-High
High
Med- Low
Med-High
High
To effect the adjustment,
the RED and BLUE
wires can be changed
on the motor.
Also,
refer
to the position
of the wires
on the
electronic
board of the unit and consult
the wiring
diagrams.
If the heating
and air conditioning
speeds are the santo, the RED
wire
must
be moved
to "UNUSED
LEADS"
on the
electronic
board and the jumper
provided
with the BLUE
wire must be used
between
the "HEAT"
and "COOL"
terminals.
The blower
start/stop
delays
can be adjusted
by positioning
the
DIP switches
on the electronic
board
as shown
in the following
figures:
DELAY
OFF
DIP SWITCH
SETTINGS
60
See
90
See
120
See
t50
See
Honeywell Control Board
120
Sec
i
6
M_n
90
See
i'
4
MIn
a.OWER O.lBLO_R O_
I
BLO_R
ON
BLOV_ZR OF_
DELAY
I
DELAy
DFJ.Ay
I
DELAY
BO See
2 Win
30 S_c
'
1 Min
BLOWER
ON
BLOWER
OFF BLOWER
ON
BLOV4_R Of}
oE.Y t oELA, LAY I o AY
ON AND OFF DELAYS
ARE
iNDEPENDENT
FROM EACH OTHER,
OTHER COMBINATIONS
ARE POSSIBLE.
UTEC
Control
Board
Fig. 18 - Fan Off Time Dip Switch
Settings
("X" Represents
Switch
Position)
A06462
Supply
Air Temperature
Rise Test
1. Operate
the burner
for at least 10 minutes.
2. Measure
the air temperature
in the return air plenum.
3.
Measuring
the air temperature
in the largest trunk coming
off the supply
air plenum,
just outside
the range
of radiant
heat from the heat exchanger.
12" (304.8 mm) from the ple-
num of the main take-off
is usually
sufficient.
4. The temperature
rise is calculated
by subtracting
the return
air temperature
from the supply air temperature
5. If the temperature
rise exceeds
the temperature
specified
in
Table
3, change
to the next higher
blower
speed
tap, until
the temperature
rise falls to the target or below. If the exces-
sive temperature
rise cannot
be reduced
by increasing
fan
speed,
investigate
for ductwork
obstructions,
dirty or im-
proper
air filter, overfiring
caused by excessive
pump pres-
sure or improper
nozzle sizing.
Step
4-
Limit-Control
Check
After furnace
has been in operation
for at least 15 minutes,
restrict
return-air
supply by blocking
filters or closing
return registers
and
allow furnace
to shut down
on high limit. The burner
should shut
off
and main blower
should continue
to run.
Remove
restriction
and burner
should
come
back
on in a few
minutes.
External Static Pressure
("W.C.)
Speed
High
Meal-High
Med- Low
Low
Table 6 - Air Flow - CFM
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1250
1205
1170
1115
1070
1010
93.5
825
605
1110
1075
1025
990
945
895
825
715
560
885
880
880
865
815
760
710
615
470
675
680
690
680
665
640
565
480
390
18
Advertisement
