diff --git a/check_hddtemp b/check_hddtemp
index 62c31aea30bd8cda40b59f8ac101e2fffcb364e6..074751518c84f2c1cdcb2f99ddb07bd475ab70a7 100755
--- a/check_hddtemp
+++ b/check_hddtemp
@@ -32,12 +32,17 @@ def check_hddtemp(host, drive, warn, crit):
     s.close()
     for drive_desc in res.split('||'):
 	drive_info = drive_desc.split('|')
-        drv_name = drive_info[1]
-        drv_type = drive_info[2]
-        drv_temp = int(drive_info[3])
-        drv_unit = drive_info[4] # C or F
+        if len(drive_info) == 5 and drive_info[0] == "":
+            drive_info = drive_info[1:]
+        drv_name = drive_info[0]
+        drv_type = drive_info[1]
+        drv_temp = int(drive_info[2])
+        drv_unit = drive_info[3] # C or F
 	if drv_name != drive:
 	    continue
+        if drv_unit != "C":
+            print "UNKNOWN - drive uses F, not C"
+            sys.exit(3)
 	if drv_temp >= crit:
 	    print "CRITICAL -", drv_temp, "C | temp=%d" % drv_temp
 	    sys.exit(2)