Narrative:

During IFR flight from sky to 9d4 at cruise altitude of 9000 ft MSL under youngstown approach control over tops of clouds; temperature at 3 degrees C; cloud level increased. Temperature in clouds dropped to 0 degrees C requiring pitot heat and carburetor heat. Carburetor heat could not be applied with cable stuck off. Immediate climb into clearing above cloud to avoid carburetor ice; requested 11000 ft to clear clouds. ATC reported my altitude at 9700 ft before giving clearance to 11000 ft. At 11000 ft indicated altitude with pressure altitude indicated at 11000 ft; ZOB stated my altitude at 11300 ft; expect transponder transmission in error.

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Original NASA ASRS Text

Title: SINGLE PLT OF IFR PA28 IS FORCED TO CLB ABOVE CLRED ALT DUE TO ICING CONDITIONS AND INOP CARB HEAT.

Narrative: DURING IFR FLT FROM SKY TO 9D4 AT CRUISE ALT OF 9000 FT MSL UNDER YOUNGSTOWN APCH CTL OVER TOPS OF CLOUDS; TEMP AT 3 DEGS C; CLOUD LEVEL INCREASED. TEMP IN CLOUDS DROPPED TO 0 DEGS C REQUIRING PITOT HEAT AND CARB HEAT. CARB HEAT COULD NOT BE APPLIED WITH CABLE STUCK OFF. IMMEDIATE CLB INTO CLRING ABOVE CLOUD TO AVOID CARB ICE; REQUESTED 11000 FT TO CLR CLOUDS. ATC RPTED MY ALT AT 9700 FT BEFORE GIVING CLRNC TO 11000 FT. AT 11000 FT INDICATED ALT WITH PRESSURE ALT INDICATED AT 11000 FT; ZOB STATED MY ALT AT 11300 FT; EXPECT XPONDER XMISSION IN ERROR.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.