diff --git a/ironic/conductor/manager.py b/ironic/conductor/manager.py
index bcb28f5c93..b960336416 100644
--- a/ironic/conductor/manager.py
+++ b/ironic/conductor/manager.py
@@ -1599,7 +1599,7 @@ class ConductorManager(base_manager.BaseConductorManager):
     @periodics.periodic(
         spacing=CONF.conductor.check_provision_state_interval,
         enabled=CONF.conductor.check_provision_state_interval > 0
-        and CONF.conductor.deploy_callback_timeout != 0)
+        and CONF.conductor.deploy_callback_timeout > 0)
     def _check_deploy_timeouts(self, context):
         """Periodically checks whether a deploy RPC call has timed out.
 
@@ -1607,8 +1607,6 @@ class ConductorManager(base_manager.BaseConductorManager):
 
         :param context: request context.
         """
-        # FIXME(rloo): If the value is < 0, it will be enabled. That doesn't
-        #              seem right.
         callback_timeout = CONF.conductor.deploy_callback_timeout
 
         filters = {'reserved': False,
@@ -1821,7 +1819,7 @@ class ConductorManager(base_manager.BaseConductorManager):
     @periodics.periodic(
         spacing=CONF.conductor.check_provision_state_interval,
         enabled=CONF.conductor.check_provision_state_interval > 0
-        and CONF.conductor.clean_callback_timeout != 0)
+        and CONF.conductor.clean_callback_timeout > 0)
     def _check_cleanwait_timeouts(self, context):
         """Periodically checks for nodes being cleaned.
 
@@ -1830,8 +1828,6 @@ class ConductorManager(base_manager.BaseConductorManager):
 
         :param context: request context.
         """
-        # FIXME(rloo): If the value is < 0, it will be enabled. That doesn't
-        #              seem right.
         callback_timeout = CONF.conductor.clean_callback_timeout
 
         filters = {'reserved': False,
@@ -2982,15 +2978,13 @@ class ConductorManager(base_manager.BaseConductorManager):
     @periodics.periodic(
         spacing=CONF.conductor.check_provision_state_interval,
         enabled=CONF.conductor.check_provision_state_interval > 0
-        and CONF.conductor.inspect_wait_timeout != 0)
+        and CONF.conductor.inspect_wait_timeout > 0)
     def _check_inspect_wait_timeouts(self, context):
         """Periodically checks inspect_wait_timeout and fails upon reaching it.
 
         :param context: request context
 
         """
-        # FIXME(rloo): If the value is < 0, it will be enabled. That doesn't
-        #              seem right.
         callback_timeout = CONF.conductor.inspect_wait_timeout
 
         filters = {'reserved': False,
diff --git a/ironic/conf/conductor.py b/ironic/conf/conductor.py
index 63c607e3b3..494317f8d2 100644
--- a/ironic/conf/conductor.py
+++ b/ironic/conf/conductor.py
@@ -60,6 +60,7 @@ opts = [
                       'in seconds. Set to 0 to disable checks.')),
     cfg.IntOpt('deploy_callback_timeout',
                default=1800,
+               min=0,
                help=_('Timeout (seconds) to wait for a callback from '
                       'a deploy ramdisk. Set to 0 to disable timeout.')),
     cfg.BoolOpt('force_power_state_during_sync',
@@ -149,6 +150,7 @@ opts = [
                       'configdrive_use_object_store is True.')),
     cfg.IntOpt('inspect_wait_timeout',
                default=1800,
+               min=0,
                help=_('Timeout (seconds) for waiting for node inspection. '
                       '0 - unlimited.')),
     cfg.BoolOpt('automated_clean',
@@ -184,6 +186,7 @@ opts = [
                        'maintenance will make the process continue.')),
     cfg.IntOpt('clean_callback_timeout',
                default=1800,
+               min=0,
                help=_('Timeout (seconds) to wait for a callback from the '
                       'ramdisk doing the cleaning. If the timeout is reached '
                       'the node will be put in the "clean failed" provision '
diff --git a/releasenotes/notes/disable_periodic_task-590a91c0a5235cfb.yaml b/releasenotes/notes/disable_periodic_task-590a91c0a5235cfb.yaml
new file mode 100644
index 0000000000..a613be6651
--- /dev/null
+++ b/releasenotes/notes/disable_periodic_task-590a91c0a5235cfb.yaml
@@ -0,0 +1,8 @@
+---
+fixes:
+  - |
+    Fixes periodic task initialization options to prevent a negative number.
+
+    If "[conductor]clean_callback_timeout","[conductor]inspect_wait_timeout"
+    and "[conductor]inspect_wait_timeout" are a negative value will cause an
+    error on start up from now on.
\ No newline at end of file