Carrier 59SC6A Installation Instructions Manual page 61

59SC6A: Installation, Start-up, Operating and Service and Maintenance Instructions
WARNING
!
FIRE HAZARD
Failure to follow this warning could result in personal injury, death,
and/or property damage.
Manifold pressure tap set screw must be tightened and 1/8-in. NPT pipe
plug must be installed to prevent gas leaks.
c. Tighten set screw on manifold tower pressure tap with 3/32-in.
hex wrench, or if 1/8-in. NPT plug was removed, apply pipe
dope sparingly to end of plug and reinstall in the gas valve.
d. Turn gas valve ON/OFF switch to ON.
e. Check for gas leaks and verify furnace operation.
Adjust Temperature Rise
NOTE: Blower door must be installed when taking temperature rise
reading. Leaving blower door off will result in incorrect temperature
measurements, due to possible changes in duct static pressure and
airflow.
CAUTION
!
FURNACE DAMAGE HAZARD
- Failure to follow this caution may result in:
Overheating the heat exchangers or condensing flue gases in
heat exchanger areas not designed for condensate.
- Shortened furnace life.
- Component damage.
Temperature rise must be within limits specified on furnace rating plate.
Recommended operation is at midpoint of rise range or slightly above.
Set temperature rise. The furnace must operate within the temperature
rise ranges specified on the furnace rating plate. Do not exceed
temperature rise range specified on unit rating plate. Determine the
temperature rise as follows:
NOTE: Blower door must be installed when taking temperature rise
reading. Leaving blower door off will result in incorrect temperature
measurements, due to possible changes in duct static pressure and
airflow.
1. Place duct thermometers in return and supply ducts as close to
furnace as possible. Be sure thermometers do not "see" heat
exchangers so that radiant heat does not affect thermometer
readings. This is particularly important with straight run ducts.
2. When thermometer readings
temperature from supply-air temperature to determine temperature
rise.
If the temperature rise is outside this range, check the following:
a. Gas input rate.
b. Derate for altitude applicable.
c. Return and supply ducts for excessive restrictions causing static
pressures greater than 0.50-in. w.c. (125 Pa)
WARNING
!
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury or death.
Blower access door switch opens 115-V power to control. No
component operation can occur unless switch is closed. Caution must
be taken when manually closing this switch.
3. Adjust air temperature rise by adjusting blower speed. Increase
blower speed to reduce temperature rise. Decrease blower speed to
increase temperature rise
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
stabilize, subtract return-air
4. Turn thermostat down below room temperature and remove blower
access door.
5. Refer to the FURNACE CONTROL PROGRAMMING AND
NAVIGATION section of this manual for instructions on adjusting
the blower speed.
6. Repeat steps a through e until temperature rise is within range on
rating plate.
7. When correct input rate and temperature rise is achieved, turn gas
valve ON/OFF switch to OFF.
!
FIRE HAZARD
Failure to follow this warning could result in personal injury, death,
and/or property damage.
Reinstall manifold pressure tap plug in gas valve to prevent gas leak.
8. Remove manometer or similar device from gas valve.
9. Reinstall manifold pressure tap plug in gas valve.
!
FURNACE OVERHEATING HAZARD
Failure to follow this caution may result in reduced furnace life.
Recheck temperature rise. It must be within limits specified on the
rating plate. Recommended operation is at the mid-point of rise range
or slightly above.
Adjust Heating Blower-OFF Delay
1. The blower-OFF delay has four adjustable settings from 90 sec to
180 sec. Refer to the FURNACE CONTROL PROGRAMMING
AND NAVIGATION section of this manual for instructions.
Factory off delay setting is 120 sec.
2. Set airflow CFM for cooling. See
filter).
3. Adjust cooling blower-OFF delay. Refer to the FURNACE
CONTROL PROGRAMMING AND NAVIGATION section of
this manual for instructions.
Check Safety Controls
The flame sensor, gas valve, and pressure switch were all checked in the
Start-up procedure section as part of normal operation.
1. Check Main Limit Switch
This control shuts off combustion system and energizes
air-circulating blower motor, if furnace overheats. By using this
method to check the temperature limit control, it can be established
that the limit is functioning properly and that the limit will operate
if there is a restricted return-air supply or motor failure. If the limit
control does not function during this test, the cause must be
determined and corrected.
a. Run furnace for at least 5 minutes.
b. Gradually block off return air with a piece of cardboard or sheet
metal until the limit trips.
c. Unblock return air to permit normal circulation.
d. Burners will re-light when furnace cools down.
2. Check Pressure Switch(es)
This control proves operation of the draft inducer blower.
a. Turn off 115-V power to furnace.
b. 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 low
pressure switch is functioning properly, hot surface igniter
should NOT glow and control diagnostic light flashes a status
61
WARNING
WARNING
Table 18-Air Delivery CFM (with