Terry McWilliams
Deer Park, Texas
From 12 Tons to 8.5: Reengineering Comfort in a Historic Houston Landmark
A century-old Houston landmark meets modern building science through performance testing, precision HVAC design, and humidity control.
The problem
The homeowners reported high indoor humidity, condensation issues, excessive HVAC noise, and unusually high energy bills. The century-old residence had four HVAC systems totaling 12 tons, raising concerns about equipment sizing, airflow, moisture management, and overall performance.
The process
Site evaluation, blower door, and HVAC testing guided new ductwork, three systems totaling 8.5 tons, and whole-home dehumidification.
Tools used · 20 across 7 categories
Refrigerant & Charge
- Wireless Probes & Sensors
- Vacuum & Micron Gauges
- Scales
Airflow & Air Quality
- Air & Gas Manometers / Pressure Gauges
- Airflow Indicators & Measurement
- Flow Hood
- Temperature & Humidity Meters
- IAQ Instruments & Monitors
Building Performance
The result
The transformation delivered what matters most to the homeowner: a quieter, healthier, more comfortable living environment with greater control and lower operating costs.
Improved temperature consistency throughout the home, significantly better humidity management, and reduced condensation concerns have made everyday living more comfortable. Enhanced air filtration, ventilation, and reduced duct leakage contribute to cleaner, fresher indoor air, while quieter operation and precise temperature control allow comfort to be tailored to different areas of the residence.
With more efficient operation and lower energy bills, the homeowner can enjoy the benefits of modern comfort technology without compromising the character of this century-old Houston landmark.
The result is more than better heating and cooling. It's a healthier, quieter, more comfortable home that performs as thoughtfully as it was originally designed.
Equipment installed
Installed two Armstrong Air variable-capacity, dual-fuel heat pump systems with multistage furnaces and zoning controls, plus one single-stage HVAC system, totaling 8.5 tons of cooling capacity. The project included a completely redesigned duct distribution system, a dedicated whole-home ventilating dehumidifier, professional duct cleaning, and Aeroseal technology to address duct leakage in otherwise inaccessible areas. These improvements were designed to enhance airflow, temperature consistency, humidity management, indoor air quality, and overall system performance while reducing installed cooling capacity by approximately 29%.
Measurable results
29% Reduction in Installed Cooling Capacity: Reduced from four systems totaling 12 tons to three systems totaling 8.5 tons through performance-based system design.
Thousands in Consumer Rebates: Homeowners received several thousand dollars in energy-efficiency rebates through CenterPoint Energy.
Hundreds in Energy Savings: Homeowners reported several hundred dollars in reduced summer energy bills compared with their previous costs.
Improved Temperature Consistency: More even temperatures throughout the residence, with precise zoning and variable-capacity operation providing greater comfort and individualized control.
Improved Humidity Management: Indoor humidity is now maintained at safe, comfortable levels, addressing a major source of discomfort and previous condensation concerns.
Noticeably quieter HVAC operation, improved air distribution, and enhanced indoor air quality contribute to a more peaceful and comfortable living environment.
Project gallery
8 photosSee the difference
Terry McWilliams
Deer Park, Texas