diff --git a/cdsobs/api_rest/endpoints.py b/cdsobs/api_rest/endpoints.py
index ab22d02..5a364bd 100644
--- a/cdsobs/api_rest/endpoints.py
+++ b/cdsobs/api_rest/endpoints.py
@@ -6,15 +6,12 @@
 import sqlalchemy.orm
 from fastapi import APIRouter, Depends, HTTPException
 
-from cdsobs.api_rest.models import RetrievePayload
 from cdsobs.cdm.lite import cdm_lite_variables
 from cdsobs.config import CDSObsConfig, validate_config
 from cdsobs.observation_catalogue.repositories.cads_dataset import CadsDatasetRepository
 from cdsobs.observation_catalogue.repositories.catalogue import CatalogueRepository
-from cdsobs.retrieve.retrieve_services import (
-    _get_catalogue_entries,
-    get_urls_and_check_size,
-)
+from cdsobs.retrieve.models import RetrieveArgs
+from cdsobs.retrieve.retrieve_services import _get_catalogue_entries, get_urls
 from cdsobs.service_definition.api import get_service_definition
 from cdsobs.service_definition.service_definition_models import ServiceDefinition
 from cdsobs.storage import S3Client
@@ -31,6 +28,16 @@ class HttpAPISession:
 
 
 def session_gen() -> Iterator[HttpAPISession]:
+    cdsobs_config = get_config()
+    try:
+        catalogue_session = get_database_session(cdsobs_config.catalogue_db.get_url())
+        session = HttpAPISession(cdsobs_config, catalogue_session)
+        yield session
+    finally:
+        session.catalogue_session.close()
+
+
+def get_config() -> CDSObsConfig:
     if "CDSOBS_CONFIG" in os.environ:
         cdsobs_config_yml = Path(os.environ["CDSOBS_CONFIG"])
     else:
@@ -38,12 +45,7 @@ def session_gen() -> Iterator[HttpAPISession]:
     if not Path(cdsobs_config_yml).exists():
         raise ConfigNotFound()
     cdsobs_config = validate_config(cdsobs_config_yml)
-    try:
-        catalogue_session = get_database_session(cdsobs_config.catalogue_db.get_url())
-        session = HttpAPISession(cdsobs_config, catalogue_session)
-        yield session
-    finally:
-        session.catalogue_session.close()
+    return cdsobs_config
 
 
 def make_http_exception(
@@ -58,13 +60,12 @@ def make_http_exception(
     return http_exception
 
 
-@router.post("/get_object_urls_and_check_size")
-def get_object_urls_and_check_size(
-    retrieve_payload: RetrievePayload,
+@router.post("/get_object_urls")
+def get_object_urls(
+    retrieve_args: RetrieveArgs,
     session: Annotated[HttpAPISession, Depends(session_gen)],
 ) -> list[str]:
     # Query the storage to get the URLS of the files that contain the data requested
-    retrieve_args = retrieve_payload.retrieve_args
     try:
         catalogue_repository = CatalogueRepository(session.catalogue_session)
         entries = _get_catalogue_entries(catalogue_repository, retrieve_args)
@@ -78,9 +79,7 @@ def get_object_urls_and_check_size(
         )
     s3client = S3Client.from_config(session.cdsobs_config.s3config)
     try:
-        object_urls = get_urls_and_check_size(
-            entries, retrieve_args, retrieve_payload.config.size_limit, s3client.base
-        )
+        object_urls = get_urls(entries, s3client.base)
     except SizeError as e:
         raise HTTPException(status_code=500, detail=dict(message=f"Error: {e}"))
     except Exception as e:
diff --git a/cdsobs/api_rest/models.py b/cdsobs/api_rest/models.py
deleted file mode 100644
index b7e10e1..0000000
--- a/cdsobs/api_rest/models.py
+++ /dev/null
@@ -1,12 +0,0 @@
-from pydantic import BaseModel
-
-from cdsobs.retrieve.models import RetrieveArgs
-
-
-class RetrieveConfig(BaseModel):
-    size_limit: int = 10000
-
-
-class RetrievePayload(BaseModel):
-    retrieve_args: RetrieveArgs
-    config: RetrieveConfig
diff --git a/cdsobs/ingestion/serialize.py b/cdsobs/ingestion/serialize.py
index 6a4f7dd..f3f9696 100644
--- a/cdsobs/ingestion/serialize.py
+++ b/cdsobs/ingestion/serialize.py
@@ -20,7 +20,6 @@
 )
 from cdsobs.netcdf import (
     get_encoding_with_compression,
-    get_encoding_with_compression_xarray,
 )
 from cdsobs.service_definition.service_definition_models import ServiceDefinition
 from cdsobs.storage import StorageClient
@@ -277,20 +276,21 @@ def batch_to_netcdf(
         output_dir,
         f"{new_dataset_name}_{source}_{time_batch.year}_{time_batch.month:02d}.nc",
     )
-    for field in homogenised_data:
-        if homogenised_data[field].dtype == "string":
-            homogenised_data[field] = homogenised_data[field].str.encode("UTF-8")
-    homogenised_data_xr = homogenised_data.to_xarray()
-    if service_definition.global_attributes is not None:
-        homogenised_data.attrs = {
-            **homogenised_data.attrs,
-            **service_definition.global_attributes,
-        }
-    encoding = get_encoding_with_compression_xarray(
-        homogenised_data_xr, string_transform="str_to_char"
+    encoding = get_encoding_with_compression(
+        homogenised_data, string_transform="str_to_char"
     )
-    logger.info(f"Writing de-normalized and CDM mapped data to {output_path}")
-    homogenised_data_xr.to_netcdf(
-        output_path, encoding=encoding, engine="netcdf4", format="NETCDF4"
+    # Encode dates
+    attrs = dict()
+    for varname in homogenised_data.columns:
+        var_series = homogenised_data[varname]
+        if var_series.dtype.kind == "M":
+            homogenised_data[varname] = datetime_to_seconds(var_series)
+        attrs[varname] = dict(units=constants.TIME_UNITS)
+
+    write_pandas_to_netcdf(
+        output_path,
+        homogenised_data,
+        encoding,
+        attrs=service_definition.global_attributes,
     )
     return output_path
diff --git a/cdsobs/retrieve/api.py b/cdsobs/retrieve/api.py
index 675571c..20ce394 100644
--- a/cdsobs/retrieve/api.py
+++ b/cdsobs/retrieve/api.py
@@ -9,7 +9,7 @@
 from cdsobs.retrieve.models import RetrieveArgs
 from cdsobs.retrieve.retrieve_services import (
     _get_catalogue_entries,
-    get_urls_and_check_size,
+    get_urls,
 )
 from cdsobs.service_definition.api import get_service_definition
 from cdsobs.utils.logutils import get_logger
@@ -52,9 +52,7 @@ def retrieve_observations(
     with get_database_session(catalogue_url) as session:
         catalogue_repository = CatalogueRepository(session)
         entries = _get_catalogue_entries(catalogue_repository, retrieve_args)
-        object_urls = get_urls_and_check_size(
-            entries, retrieve_args, size_limit, storage_url
-        )
+        object_urls = get_urls(entries, storage_url)
         global_attributes = get_service_definition(
             retrieve_args.dataset
         ).global_attributes
diff --git a/cdsobs/retrieve/retrieve_services.py b/cdsobs/retrieve/retrieve_services.py
index 23cf04a..aa78335 100644
--- a/cdsobs/retrieve/retrieve_services.py
+++ b/cdsobs/retrieve/retrieve_services.py
@@ -109,10 +109,8 @@ def filter_retrieve_constraints(
     return ConstraintsSchema.from_table(retrieve_table)
 
 
-def get_urls_and_check_size(
+def get_urls(
     entries: Sequence[Catalogue],
-    retrieve_args: RetrieveArgs,
-    size_limit: int,
     storage_url: str,
 ) -> list[str]:
     """
@@ -122,7 +120,6 @@ def get_urls_and_check_size(
     are garbage collected.
     """
     object_urls = [f"{storage_url}/{e.asset}" for e in entries]
-    _check_data_size(entries, retrieve_args, size_limit)
     return object_urls
 
 
diff --git a/tests/retrieve/test_adaptor.py b/tests/retrieve/test_adaptor.py
index 48b7e31..fe0044b 100644
--- a/tests/retrieve/test_adaptor.py
+++ b/tests/retrieve/test_adaptor.py
@@ -130,6 +130,7 @@ def test_adaptor_gnss(tmp_path):
         "year": ["2000"],
         "month": ["10"],
         "day": [f"{i:02d}" for i in range(1, 32)],
+        "area": ["50", "-10", "20", "10"],
     }
     test_form = {}
     # + "/v1/AUTH_{public_user}" will be needed to work with S3 ceph public urls, but it
diff --git a/tests/test_http_api.py b/tests/test_http_api.py
index 2d4e0b5..cd8a958 100644
--- a/tests/test_http_api.py
+++ b/tests/test_http_api.py
@@ -17,27 +17,24 @@ def test_session() -> HttpAPISession:
     app.dependency_overrides[session_gen] = test_session
 
     payload = {
-        "retrieve_args": {
-            "dataset": "insitu-observations-gnss",
-            "params": {
-                "dataset_source": "IGS_R3",
-                "stations": ["AREQ00PER"],
-                "latitude_coverage": (-90.0, 0.0),
-                "longitude_coverage": (-180.0, 0.0),
-                "format": "netCDF",
-                "variables": [
-                    "precipitable_water_column",
-                    "precipitable_water_column_total_uncertainty",
-                ],
-                "year": ["2000"],
-                "month": ["10"],
-                "day": [f"{i:02d}" for i in range(1, 32)],
-            },
+        "dataset": "insitu-observations-gnss",
+        "params": {
+            "dataset_source": "IGS_R3",
+            "stations": ["AREQ00PER"],
+            "latitude_coverage": (-90.0, 0.0),
+            "longitude_coverage": (-180.0, 0.0),
+            "format": "netCDF",
+            "variables": [
+                "precipitable_water_column",
+                "precipitable_water_column_total_uncertainty",
+            ],
+            "year": ["2000"],
+            "month": ["10"],
+            "day": [f"{i:02d}" for i in range(1, 32)],
         },
-        "config": {"size_limit": 1000000},
     }
 
-    response = client.post("/get_object_urls_and_check_size", json=payload)
+    response = client.post("/get_object_urls", json=payload)
     assert response.status_code == 200
     assert response.json() == [
         "http://127.0.0.1:9000/cds2-obs-dev-insitu-observations-gnss/"