diff --git a/pyaerocom/aeroval/coldatatojson_engine.py b/pyaerocom/aeroval/coldatatojson_engine.py
index 935b36372..e83d63442 100644
--- a/pyaerocom/aeroval/coldatatojson_engine.py
+++ b/pyaerocom/aeroval/coldatatojson_engine.py
@@ -50,7 +50,9 @@ def run(self, files):
         for file in files:
             logger.info(f"Processing: {file}")
             coldata = ColocatedData(file)
-            self.process_coldata(coldata)
+            self.process_coldata(
+                coldata
+            )  # Lb: possibly want a flag in the coldata objects which processes the profile coldata objects for viz
             converted.append(file)
         return converted
 
@@ -160,10 +162,12 @@ def process_coldata(self, coldata: ColocatedData):
 
         use_country = True if regions_how == "country" else False
 
-        data = _init_data_default_frequencies(coldata, freqs)
+        data = _init_data_default_frequencies(
+            coldata, freqs
+        )  # LB: Here not all coldata has nans but data is all nans for all freqs
 
         if annual_stats_constrained:
-            data = _apply_annual_constraint(data)
+            data = _apply_annual_constraint(data)  # LB: maybe this is setting everything to nans
 
         if not diurnal_only:
             logger.info("Processing statistics timeseries for all regions")
@@ -189,6 +193,7 @@ def process_coldata(self, coldata: ColocatedData):
                     ts_file, stats_ts, obs_name, var_name_web, vert_code, model_name, model_var
                 )
 
+            breakpoint()
             logger.info("Processing heatmap data for all regions")
             hm_all = _process_heatmap_data(
                 data,
diff --git a/pyaerocom/colocateddata.py b/pyaerocom/colocateddata.py
index aca715534..45aa375ab 100644
--- a/pyaerocom/colocateddata.py
+++ b/pyaerocom/colocateddata.py
@@ -1056,7 +1056,15 @@ def rename_variable(self, var_name, new_var_name, data_source, inplace=True):
 
     @staticmethod
     def _aerocom_savename(
-        obs_var, obs_id, mod_var, mod_id, start_str, stop_str, ts_type, filter_name, vertical_layer
+        obs_var,
+        obs_id,
+        mod_var,
+        mod_id,
+        start_str,
+        stop_str,
+        ts_type,
+        filter_name,
+        vertical_layer=None,  # LB: testing this because I don't want this to be required
     ):
         if (
             not vertical_layer is None