Unitary products group G8C 50, Руководство по установке

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17
Diagnostics
The electronic furnace control supplied on this
furnace is equipped with a diagnostic light, which
flashes when there is a service problem with the
furnace. The number of times the light flashes
indicates the location of the problem, as listed
below:
Steady off - Normal operation
One flash - False flame sense - Check for stuck
open gas valve.
Two flashes - Pressure switch stuck closed. Check
for shorted wires, bad pressure switch.
Three flashes - Pressure switch failed to close -
Check vent blower, pressure switch, vent blockage,
disconnected pressure hose.
Four flashes - Limit switch open - Check for open
limit switch, loose connections in limit circuit.
Five flashes - Rollout switch open - Check for open
rollout switches, loose connections in rollout switch
circuit.
Six flashes - One hour pressure switch lockout -
Pressure switch has cycled four times in a single call
for heat - Check for vent blockage, loose connec-
tions in pressure switch circuit.
Seven flashes - One-hour ignition lockout - Burner
failed to light in three tries - Check gas flow, gas
pressure, gas valve operation, flame sensor.
Eight flashes - One-hour ignition lockout - Five
recycles in a single call for heat. Check gas flow, gas
pressure, and gas valve operation, flame sensor.
Nine flashes - Reversed line voltage polarity -
Check incoming power wiring for proper polarity.
Eleven flashes –Jumper wire on control board is
disconnected.
Steady on - Gas valve energized with no call for
heat from thermostat, or, control failure.
WIRING DIGRAM