Checklist - Carrier 58SMA Operating Instructions Manual

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.
Step 2—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 main furnace door and disconnect inducer motor lead
wires 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 ignitor
should NOT glow, and control center diagnostic light flashes
a 31 fault. If hot surface ignitor glows 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 furnace.
6. Reconnect inducer motor leads, reinstall main furnace door,
and turn on 115-v power supply.
1. Put away tools and instruments. Clean up debris.
2. Verify manual reset switch has continuity.
3. Verify that blower and control 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.
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CHECKLIST