diff --git a/TM/io.py b/TM/io.py
index cdca9a9a0c95a558b275e9a72ff8bd22de57868f..987a96704a94d4c33d849cb2bce83ca7f34d5162 100644
--- a/TM/io.py
+++ b/TM/io.py
@@ -1241,6 +1241,8 @@ def preload_chunk(chunkId, chunkTime, chunkLength, raw=True, processed=True, std
         if ret is not None:
             return ret
 
+    logger.debug('Preloading chunk %d (time %s, length %d)' % (chunkId, chunkTime, chunkLength))
+
     # Get processed chunk from archive and calculate windowed std
     try:
         chunkStream, chunkStream_BP, stdWindowed = \
@@ -1445,6 +1447,8 @@ def preload_template(templateId, templateTime, templateLength, mag):
         if templateStream is not None:
             return templateStream, None
 
+    logger.debug('Preloading template %d %s' % (templateId+1, templateTime))
+
     dir_tp_mseed = os.path.join(config.directory, 'templates_mseed')
     dir_tp_plots = os.path.join(config.directory, 'templates_plot_processed')
     os.makedirs(dir_tp_mseed, exist_ok=True)