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Tempstar Furnace Error Codes

Error Codes What this means How to fix it
Heartbeat LED pattern on solid The control is locked out and will auto-reset after 1 hour. Reset power to clear the lockout.
Two LED flashes Pressure switch didn’t open. Obstructed pressure tubing; a pressure switch that’s stuck closed.
Three LED flashes The low-pressure switch did not close or has reopened. Proper vent sizing; air leak; restricted vent; clogged condensate drain; low input gas pressure; excessive wind; improper pressure switch wiring; water in vent piping; disconnected or obstructed pressure tubing.
Four LED flashes Limit circuit fault. Loose blower wheel; defective switch or connections; improper minimum- or maximum-heat gas input adjustment; dirty filter or restricted duct system; improper limit switch.
Five LED flashes Abnormal flame-proving signal. Leaky gas valve; stuck-open gas valve.
Six LED flashes Ignition proving a failure. Low inlet gas pressure; control ground continuity; gas valve defect; defective hot surface igniter; oxide buildup on the flame sensor; inadequate flame carryover; flame sensor mustn’t be grounded.
Seven LED flashes Limit circuit lockout. Control will auto-reset after 3 hours. Refer to status code #4.
Eight LED flashes Gas heating lockout. Gas valve stuck closed on control.
Nine LED flashes Medium pressure switch, high-pressure switch, or PSR relay didn’t close or was reopened. Refer to status code #3.
Ten LED flashes Polarity. Correct line voltage polarity.
Status codes 1 + 2 Blower on after power up. Normal operation.
Status codes 1 + 5 Blower motor lockout. Control will auto-reset after 3 hours. Refer to status code #4 + 1.
Status codes 3 + 5 Gas valve fault. RED, YELLOW, or ORANGE wire at the gas valve.
Status codes 4 + 1 Blower motor fault. Blower failed to reach 250 RPM, or the blower failed to communicate within the prescribed time limits.
Status codes 4 + 2 Inducer motor fault. Proper vent sizing; restricted vent; failed inducer motor; improper motor wiring; a blockage in the tubing to the pressure switch assembly.
Status codes 4 + 3 The low or medium pressure switch is open while the medium or high-pressure switch is closed. Low inlet gas pressure; clogged condensate drain; improper pressure switch wiring; water in vent piping; low or medium pressure switch stuck open; disconnected or obstructed pressure tubing.
Status codes 6 + 1 Ignition lockout. Control will auto-reset after 3 hours. Refer to status code #6.
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