What was found
AT FL 270, NR 1 BLEED FAIL EICAS MESSAGE WITH AMBER X OVER NR 1 BLEED THIS OCCURRED AFTER ENTERING ICE CONDITION WITH EQUIPMENT ON. NR 1 BLEED WAS RESET, BLEED NR 1 FAILED MSG REMAINED. AMBER X OVER THE VALVE CLEARED AND BLEED PRESSURE RETURNED TO 40 PSI. CABIN PRESSURE WAS REGAINED AND EXITED ICING CONDITION. BLEED PRESSURE WAS FLUXUATING FROM 45-12 PSI FROM THE NR 1 BLEED IS INOPERATIVE AND ON MEL. APU BLEED WAS USED AT 15,000 FT AS A BACK UP. R & R NR 1 ENGINE TORQUE MOTOR CONTROLLER IAW 36-11-06. PERFORMED BLEED SYSTEM NR 1 AND NR 2 FUNCTIONAL TEST WITH HIGH POWER RUN IAW AMM 36-00-00. ALL PRESSURES, TEMPERATURE STABLE FOR SYS 1 AND 2. BLEED NR 2 WAS ALSO CORRECTED BY REPLACING THE HIGH PRESSURE VALVE.