Operating instructions
SUBBASE
TERMINALS WiTH
THERMOSTATREMOVED
24-VOLT
TERMINAL BLOCK
EXAMPLE 5 0 AMPS ON AMMETER = 0 5 AMPS FOR THERMOSTAT SETTING
/0 TURNS AROUND JAWS
A80201
Fig. 60--Amp Draw Check with Ammeter
Step 5--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.
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 offburners, 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 duct or motor failure. If limit control does not function
during this test, cause must be determined and con'ected.
CHECK PRESSURE SWITCH
This control proves operation of draft inducer. Check switch
operation as follows:
i. Turn off 115-v power to furnace.
2. Remove outer furnace door and disconnect inducer motor
from wire harness.
3. Turn on l15-v power to furnace.
4. Set thermostat to "call for heat" and wait 1 minute. When
pressure switch is functioning properly, hot surfiace igniter
should NOT glow, and control status code LED flashes a
Stares (?ode 31. If hot surfiace igniter glows when inducer
motor is disconnected, shut furnace down immediately. De-
termine reason pressure switch did not function properly and
correct condition.
5. Turn off l15-v power to furnace.
6. Reconnect inducer motor leads, reinstall main furnace door,
and turn on 115-v power supply.
Step 6--Checklist
i. Put away tools and instruments. Clean up debris.
2. Verify flame-rollout manual reset switch has continuity.
3. Verity that blower and main outer access doors are properly
installed.
4. Cycle test furnace with room themmstat.
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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