As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AT ALTITUDE WITH BLEED AIR ON, TEMP CONTROL KNOB TO FULL HOT. VERY LIMITED AMOUNT OF HEATED AIR ENTERING CABIN. OUTSIDE AIR 19C SURFACE TEMPERATURE ON GROUND AROUND -6C. AT CRUISE ITT 610C. CABIN HEAT DOES NOT START FLOWING TILL APPROXIMATELY 15-20 SEC AFTER TAKEOFF EVEN WITH BLEED AIR ON.