# Reasons for error "requests.exceptions.ChunkedEncodingError: ('Connection broken:"

**URL:** <https://forum.ecmwf.int/t/reasons-for-error-requests-exceptions-chunkedencodingerror-connection-broken/14163>\
**Category:** API\
**Tags:** api, cds, c3s, era5\
**Created:** [14 September 2025 18:51 UTC](https://forum.ecmwf.int/t/reasons-for-error-requests-exceptions-chunkedencodingerror-connection-broken/14163 "2025-09-14T18:51:41Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![Luis\_Lazcano](https://forum.ecmwf.int/letter_avatar_proxy/v4/letter/l/7feea3/32.png) [@Luis\_Lazcano](https://forum.ecmwf.int/u/Luis_Lazcano)\
**Post date:** [14 September 2025 18:51 UTC](https://forum.ecmwf.int/t/reasons-for-error-requests-exceptions-chunkedencodingerror-connection-broken/14163/1 "2025-09-14T18:51:42Z")

</div>

I am currently donwloading air temperature for ERA5 levels using the API in windows and I constantly suffer from the error “requests.exceptions.ChunkedEncodingError: (‘Connection broken: IncompleteRead(10223616 bytes read, 2720791 more expected)’, IncompleteRead(10223616 bytes read, 2720791 more expected))”

Suddenly the download speed drops dramatically and this causes the broken connection. Although I checked and my internet speed haven’t change, nor it has errors related to downloading speed. Has anyone else experience this problem and found a solution?