diff --git a/netrender/master.py b/netrender/master.py
index d1b8fde2fb8d037b5fd572ef71d98c03bfb6102c..d70a36ef15cd30631a7c238779ef3ef88380c289 100644
--- a/netrender/master.py
+++ b/netrender/master.py
@@ -455,7 +455,7 @@ class RenderHandler(http.server.BaseHTTPRequestHandler):
                             message = frame.serialize()
                         else:
                             # no such frame
-                            self.send_heat(http.client.NO_CONTENT)
+                            self.send_head(http.client.NO_CONTENT)
                             return
                     else:
                         message = job.serialize()