Solving Unusual HVAC Challenges: A Case Study from San Antonio's Heat Wave 2023

Introduction

In 2023, during a record-breaking summer in San Antonio, with 74 days of triple-digit temperatures surpassing the all-time record of 59 days set in 2009, one of our long-standing customers faced a unique challenge with his air conditioning system. Despite regular maintenance by our team, the problem this year was markedly different and required a specialized approach.

Customer’s Challenge

The customer’s three-car garage, which is tandem or double-length on one side, was experiencing unusually high temperatures, reaching up to 100 degrees during the day. Despite the garage having a very large ceiling at nearly 14 feet high, the heat was not dissipating overnight. This issue was exacerbated by the garage’s high ceilings and different elevations typical in the area. Additionally, the internal house walls adjacent to the garage absorbed the heat, increasing the thermal load inside the home and making the living spaces uncomfortably warm.

Compounding the Problem

The customer’s car, equipped with a cabin interior thermal protection system, was an unexpected contributor to the garage’s heat. This feature, designed to protect the car’s interior, pets, or persons from overheating, automatically activated the car’s air conditioning when internal temperatures soared. Unfortunately, this well-intended feature was counterproductive, as it expelled hot air into the garage, thus worsening the garage’s overall temperature. Moreover, this cycle caused his Tesla Model 3 to consume more electricity, adding to energy costs.

Identifying the Solution

To effectively address these challenges, we decided on a strategic solution to manage the various issues presented by the garage’s unique environment.

High-Efficiency Mini-Split System: We installed an American Standard heat pump mini-split system renowned for its energy efficiency and precise temperature control. This system was specifically chosen to cool the large garage space down to a comfortable 80/85 degrees, even during peak heat.

We were able to achieve several significant benefits:

• Targeted Cooling: The mini-split system directly cools the garage area, maintaining a steady temperature of 80 degrees, significantly reducing heat build-up during the day.
• Cost-Effective Operation: Our customer has noted that the system runs on just pennies a day in terms of electricity costs, thanks to the high efficiency of the mini-split design.
• Enhanced Usability of Space: With the reduced temperature, the garage is now a viable space for storing temperature-sensitive household items that previously could not be kept there due to the excessive heat. His wife really appreciates the added storage space.

Results

Post-installation, the garage temperatures dropped significantly, even during peak heat periods, and the internal house walls adjacent to the garage remained noticeably cooler. The customer reported a decrease in overall energy consumption, and the wear and tear on the car’s AC system also diminished, leading to longer battery life and reduced electricity usage.

Conclusion

This case highlights the importance of understanding and adapting to unique HVAC challenges. At Dunn Wright Heating & Cooling, we pride ourselves on our ability to diagnose complex issues and implement effective, tailored solutions that resolve immediate discomfort and contribute to long-term energy efficiency and cost savings.