As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER STARTING APU AND BLEED AIR ON, COULD NOT CONTROL COCKPIT HEAT AUTO OR MANUAL. BLUE SMOKE FILLED COCKPIT. DUCT TEMPERATURE WAS 210 AND RISING WHEN BLEED AIR WAS TURNED OFF. SMOKE THEN DISAPPEARED. INVESTIGATED AND FOUND APU OVER SERVICED WITH OIL. SERVICED APU OIL TO PROPER LEVEL IAW 650 M/M 12-10-66. REMOVED AND REPLACED COCKPIT AND CABIN WATER SEPARATOR COALESCERS DUE TO OIL CONTAMINATION IAW 650 M/M12-10-01. OPS CHECKS GOOD.