diff --git a/rattail_tempmon/server.py b/rattail_tempmon/server.py
index 1968782..f5ef640 100644
--- a/rattail_tempmon/server.py
+++ b/rattail_tempmon/server.py
@@ -246,15 +246,20 @@ class TempmonServerDaemon(Daemon):
         timeout = probe.timeout_for_status(status)
         if timeout is None:
             if status == self.enum.TEMPMON_PROBE_STATUS_CRITICAL_HIGH_TEMP:
-                timeout = self.config.getint('rattail_tempmon', 'probe.default.critical_max_timeout')
+                timeout = self.config.getint('rattail_tempmon', 'probe.default.critical_max_timeout',
+                                             default=0)
             elif status == self.enum.TEMPMON_PROBE_STATUS_HIGH_TEMP:
-                timeout = self.config.getint('rattail_tempmon', 'probe.default.good_max_timeout')
+                timeout = self.config.getint('rattail_tempmon', 'probe.default.good_max_timeout',
+                                             default=0)
             elif status == self.enum.TEMPMON_PROBE_STATUS_LOW_TEMP:
-                timeout = self.config.getint('rattail_tempmon', 'probe.default.good_min_timeout')
+                timeout = self.config.getint('rattail_tempmon', 'probe.default.good_min_timeout',
+                                             default=0)
             elif status == self.enum.TEMPMON_PROBE_STATUS_CRITICAL_LOW_TEMP:
-                timeout = self.config.getint('rattail_tempmon', 'probe.default.critical_min_timeout')
+                timeout = self.config.getint('rattail_tempmon', 'probe.default.critical_min_timeout',
+                                             default=0)
             elif status == self.enum.TEMPMON_PROBE_STATUS_ERROR:
-                timeout = self.config.getint('rattail_tempmon', 'probe.default.error_timeout')
+                timeout = self.config.getint('rattail_tempmon', 'probe.default.error_timeout',
+                                             default=0)
         timeout = datetime.timedelta(minutes=timeout or 0)
         started = probe.status_started(status) or probe.status_changed
         if (self.now - started) <= timeout: