Case Studies
Case Studies
These are real field results from installations of the mechanical APR Control and the electronic APR‑E Valve. Each summary below captures the key outcome, and links to the full write-up for the job.
Every figure below is as-measured or as-reported from the field.
Precision Temperature & Humidity
Stratus Cultivation Facility
BAS trendlog data from a licensed grow facility: the APR‑E Valve on discharge-air control held ±0.88°F, a 0.128 kPa VPD range, and ±1.5% RH on standard split-system DX, through the light and dark cycles.
Indoor Agriculture · Field Trendlog Data
Virginia Healthcare Field Study
A 3-month independent side-by-side field study on two identical rooftop units. APR modulation cut total compressor starts 77% (951 to 218), held ~53% RH all summer, with zero failures since install.
Healthcare · Independent Field Study
Harvard Laser Labs
2-ton R-22 rooftop units on 100% outside air could not hold temperature or humidity for optical-table alignment, and the mirrors fogged. The APR Control delivered 15+ years of stable operation and survived an R-22 to R-407C refrigerant conversion.
Laboratories · APR Control
F1 and INDYCAR Test Lab
A 3-ton unit ran over 80% RH from short runtimes. The APR Control modulated roughly 3 tons down to about 1 ton and held 47 to 53% RH.
Laboratories · APR Control
ASHRAE Cleanroom Research (RP-1604)
Demand-based particle control across ISO Class 8 to Class 1 cleanrooms ran on a single-stage unit. The APR‑E Valve held discharge air to about ±1°F.
Cleanrooms · APR‑E Valve
Angiotech
An APR‑E7 sat on the lead 10-ton circuit of a 40-ton system. It modulated 70% to a 55°F discharge-air setpoint and held 45 to 50% RH all summer.
Cleanroom & Office · APR‑E Valve
Tower Radiology
MRI and PET-CT rooms swing from full load to idle. The APR Control holds roughly 68 to 72°F and 48 to 52% RH in compliance-critical spaces, with 20+ years of reliability across many locations.
Medical Imaging · APR Control
Pharmaceutical Packaging
A compliance-critical 100% outside-air system short cycled at 65% RH and 68°F. An APR Control retrofit dropped RH to 45% at 68°F in about one day.
Pharmaceutical · APR Control
Humidity, Reliability & Retrofits
Restaurant Modular Chiller
A badly oversized 120-ton modular chiller with four 30-ton compressors short cycled with alarms and lockouts. An APR Control on each 30-ton circuit gave 20 tons of modulation, about 67% turndown, eliminating the short cycling and lockouts and avoiding a costly tanks, pumps, and re-piping alternative.
Chillers & Restaurants · APR Control
Emergency Cold Storage
Portable cold-storage trailers using standard wall DX risked coil freeze-up at very low load. The APR Control holds suction pressure to keep the coil above freezing, and it is valued for immediate availability with no lead time.
Cold Storage · APR Control
MIT Mixed-Use
An oversized unit short cycled with high humidity in a mixed-use building housing a gallery, dance studio, and offices. The APR Control brought stable temperature and humidity and extended equipment life.
Mixed-Use · APR Control
TV Station Newsroom
A single-zone VAV system dropped discharge air below design, with coil icing and floor condensation, and it needed whisper-quiet operation. The APR Control delivered chilled-water-like performance at a fraction of the cost.
Broadcast · APR Control
Oak Ridge Center for Manufacturing Technology
A government energy test ran on the lead 6.25-ton stage of a 12.5-ton self-contained unit. The APR Control measured about 20% efficiency gain.
Government & Industrial · APR Control
Saskatoon Public Schools
District HVAC upgrades called for better comfort and reliability on tight budgets. The APR Control supports steadier operation across the district's equipment.
Schools · APR Control
Nodaway School Retrofit
A school HVAC retrofit aimed to improve comfort and ventilation-driven reliability. The APR Control adds modulation to help the equipment hold conditions.
Schools · APR Control
Marco's Pizza
A restaurant with high, variable loads needed steady comfort and fewer breakdowns. The APR Control modulates to the load for more consistent operation.
Restaurants · APR Control
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