diff --git a/R710-IPMI-TEMP/fan-speed-control.pl b/R710-IPMI-TEMP/fan-speed-control.pl
index 934b470..6df55ca 100755
--- a/R710-IPMI-TEMP/fan-speed-control.pl
+++ b/R710-IPMI-TEMP/fan-speed-control.pl
@@ -98,7 +98,7 @@ sub set_fans_servo {
                                   average(@cputemps), average(@coretemps), average(@hddtemps)),
                           average(@hddtemps));
 
-  if (!defined $weighted_temp) {
+  if (!defined $weighted_temp or $weighted_temp == 0) {
     print "Error reading all temperatures! Fallback to idrac control\n";
     set_fans_default();
     return;