diff --git a/__init__.py b/__init__.py
index 85ed017..6fb492e 100644
--- a/__init__.py
+++ b/__init__.py
@@ -87,13 +87,13 @@ class property_cache_pickle(object):
     #
     STORAGE_VERSION = 1
 
-    def __init__(self, source_instance, cache_filename, load_all_on_init=False, callback_on_data_storage=None, max_age=None, store_none_value=False):
+    def __init__(self, source_instance, cache_filename, load_all_on_init=False, callback_on_data_storage=None, max_age=None, store_on_get=True):
         self._source_instance = source_instance
         self._cache_filename = cache_filename
         self._load_all_on_init = load_all_on_init
         self._callback_on_data_storage = callback_on_data_storage
         self._max_age = max_age
-        self._store_none_value = store_none_value
+        self._store_on_get = store_on_get
         self._cached_props = None
 
     def get(self, key, default=None):
@@ -116,7 +116,7 @@ class property_cache_pickle(object):
             if self._key_filter(key) not in self._cached_props[self.DATA_TAG] or cache_old:
                 val = self._source_instance.get(key, None)
                 logger.debug("%s Loading property for '%s' from source instance (%s)", self.LOG_PREFIX, key, repr(val))
-                if val or self._store_none_value:
+                if self._store_on_get:
                     tm = int(time.time())
                     logger.debug("Storing value=%s with timestamp=%d to chache", val, tm)
                     self._cached_props[self.DATA_TAG][self._key_filter(key)] = val
@@ -132,6 +132,10 @@ class property_cache_pickle(object):
             logger.info("%s Key '%s' is not in cached_keys. Uncached data will be returned.", self.LOG_PREFIX, key)
             return self._source_instance.get(key, default)
 
+    def full_update(self):
+        self._load_source()
+        self._save_cache()
+
     def keys(self):
         """
         Method to get the available keys (from :data:`source_instance`).
@@ -163,12 +167,13 @@ class property_cache_pickle(object):
             storage_version = True
         #
         if not load_cache or uid or data_version or storage_version:
-            if self._uid() is not None and uid:
-                logger.debug("%s Source uid changed, ignoring previous cache data", self.LOG_PREFIX)
-            if self._data_version() is not None and data_version:
-                logger.debug("%s Data version increased, ignoring previous cache data", self.LOG_PREFIX)
-            if storage_version:
-                logger.debug("%s Storage version changed, ignoring previous cache data", self.LOG_PREFIX)
+            if load_cache:
+                if self._uid() is not None and uid:
+                    logger.debug("%s Source uid changed, ignoring previous cache data", self.LOG_PREFIX)
+                if self._data_version() is not None and data_version:
+                    logger.debug("%s Data version increased, ignoring previous cache data", self.LOG_PREFIX)
+                if storage_version:
+                    logger.debug("%s Storage version changed, ignoring previous cache data", self.LOG_PREFIX)
             self._cached_props = {self.AGE_TAG: {}, self.DATA_TAG: {}}
             if self._load_all_on_init:
                 self._load_source()
@@ -191,10 +196,11 @@ class property_cache_pickle(object):
         return key
 
     def _load_source(self):
+        if self._cached_props is None:
+            self._init_cache()
         logger.debug('%s Loading all data from source - %s', self.LOG_PREFIX, repr(self._source_instance.keys()))
         for key in self._source_instance.keys():
-            val = self._source_instance.get(key)
-            self._cached_props[self.DATA_TAG][self._key_filter(key)] = val
+            self._cached_props[self.DATA_TAG][self._key_filter(key)] = self._source_instance.get(key)
             self._cached_props[self.AGE_TAG][self._key_filter(key)] = int(time.time())
 
     def _save_cache(self):