Temperature always critical

Very strange value for temperature:
Synology model: “RS814”
Synology s/n: “14A0LZN498800”
DSM Version: “DSM 5.1-5022”
DSM update: Unavailable
System Status: Normal
Temperature: 72 (CRITICAL)
Power Status: Normal
System Fan Status: Normal
CPU Fan Status: Normal
Number of disks: 4
“Disk 1” (model: “WD40EFRX-68WT0N0 “) status:Normal temperature:39
“Disk 2” (model: “WD40EFRX-68WT0N0 “) status:Normal temperature:40
“Disk 3” (model: “WD40EFRX-68WT0N0 “) status:Normal temperature:40
“Disk 4” (model: “WD40EFRX-68WT0N0 “) status:Normal temperature:38
Number of RAID volume: 1
“Volume 1” status:Normal 40% used
What is the difference with disk values?