# Unable to turn off HVAC cooling in UWG Python (Southern Hemisphere summer): No temperature changes in output EPW

**URL:** <https://discourse.ladybug.tools/t/unable-to-turn-off-hvac-cooling-in-uwg-python-southern-hemisphere-summer-no-temperature-changes-in-output-epw/40663>\
**Category:** dragonfly\
**Tags:** uwg\
**Created:** [August 7, 2026, 2:20pm UTC](https://discourse.ladybug.tools/t/unable-to-turn-off-hvac-cooling-in-uwg-python-southern-hemisphere-summer-no-temperature-changes-in-output-epw/40663 "2026-08-07T14:20:52Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![rlopez](https://discourse.ladybug.tools/letter_avatar_proxy/v4/letter/r/3be4f8/32.png) [@rlopez](https://discourse.ladybug.tools/u/rlopez)\
**Post date:** [August 7, 2026, 2:20pm UTC](https://discourse.ladybug.tools/t/unable-to-turn-off-hvac-cooling-in-uwg-python-southern-hemisphere-summer-no-temperature-changes-in-output-epw/40663/1 "2026-08-07T14:20:52Z")

</div>

Hello everyone,

I am working on an Urban Weather Generator (UWG) simulation using the pure Python library. I am analyzing the Urban Heat Island (UHI) effect for a city in Chile (Southern Hemisphere) during our summer months: **December, January, February, and March**.

**The Goal:** I want to simulate a scenario where residential air conditioning (cooling) is completely turned off for specific building archetypes (e.g., `midriseapartment`).

**The Problem:** No matter how I try to disable the HVAC cooling, the output EPW temperatures remain **exactly the same** as the baseline simulation. There is zero difference in the final data.

**What I have tried so far:** I have tried programmatically modifying the cooling schedules in my Python script. Right after calling `uwg_model.generate()` and before `uwg_model.simulate()`, I iterate through `uwg_model.BEM` and `uwg_model.Sch` to force the cooling setpoint to 99°C for the target archetypes. Something like this:

Python

```auto
# Forcing AC off by setting an unreachable cooling setpoint
sch.cool = [[99.0] * 24 for _ in range(3)]

```

The code runs perfectly without any errors, but the resulting EPW shows absolutely no changes in the urban canyon temperatures or any other variable.

**My Hypothesis:** Since I am simulating December through March, is it possible that UWG’s internal DOE reference schedules are hardcoded for the Northern Hemisphere? If the model assumes December-March is “Winter”, the AC might already be turned off by default in those months. If that is the case, setting the cooling setpoint to 99°C wouldn’t make any mathematical difference, explaining why my outputs don’t change.

**My Questions:**

1. How can I successfully and definitively turn off the AC/cooling during summer using the UWG Python library?

2. Is there a Northern Hemisphere seasonal bias in the default schedules, and if so, how can I properly invert or override the seasons for a Southern Hemisphere simulation?

Any guidance, code snippets, or workarounds would be incredibly appreciated. Thank you!