1
A replacement for the 1012-830 is the
1012-831 control module. It carries
the
factory part no. 62-22694-11
and can be ordered under the kit no.
62-22694-91.
Functionally, it is the
same as the 1012-830. Units with this
control have
serial numbers
beginning with CU. -831
controls
began with
UTEC date code 9307.
There is only one physical difference
from the -830. The -831 micro-
processor has 24 pins rather than
the -830 40 pin micro.
CONTROL RESPONSES
1.
POOR EQUIPMENT
GROUNDING
• Results in erratic flame sensing
and nuisance soft lock outs.
Check for poor grounding of the
burners by measuring the
resistance from the common
transformer terminal to the sheet
metal of a burner. There should
be zero/low Ohms resistance.
Check the unit grounding by
measuring the resistance from
the furnace neutral wire to the
furnace ground wire (green or
bare copper).
FIGURE 59
HONEYWELL CIRCUIT BOARD
•
2. MAIN LIMIT OPENING
• Results in furnace shut down.
The gas valve closes, the
inducer and main blower run until
the limit resets. If the limit does
not reset, both blowers run
indefinitely.
• When the limit resets, the
inducer stops and the main
blower runs for its pre-set off
delay. After the main blower
stops, the inducer starts and
goes through a normal ignition
sequence.
3.
HEAT ASSISTED LIMIT
CONTROL (HALC) OPENING
• The control has the "self-
healing" feature to operate the
main blower if the HALC opens.
4.
PRESSURE SWITCH OPENING
• Upon a heat call the control
operates the induced draft
blower for 30 seconds before
starting the ignition sequence.
If the pressure switch contacts
do not close, the induced draft
blower continues to run for up
to 60 seconds. After 60 seconds
the control goes into soft
lock out.
5.
LOW/NO GAS PRESSURE
• With insufficient gas pressure
to generate a proper flame, the
control loses flame sensing and
goes into soft lock out.
6.
IMPROPER POLARITY
• If the control or furnace is wired
improperly, the control lights the
burners, but cannot sense the
flame current and goes into soft
lock out after 4 trials for ignition.
7.
VOLTAGE SPIKES
• Transient voltage spikes may
cause a hard lock out with -823
controls. -830 and -831 units
respond by resetting for one
second with the "OK" light off,
and then start a normal ignition
sequence.
8.
VARIATIONS IN 60 HERTZ
FREQUENCY
• The timing of the ignition
sequence changes in proportion
to the frequency variation.
9.
MOMENTARY POWER
OUTAGES
• -823 Control Boards.
There is
no effect if the outage is less
than 0.25 seconds or more than
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