Johns Hopkins University School of Medicine

Industry: Labs

A site inspection was conducted at Johns Hopkins’ Cancer Research Building I to assess the condition of twelve SEMCO True 3Å wheels installed in 2000. The wheels have operated continuously for approximately 16 years with minimal maintenance interruptions. The inspection evaluated structural integrity, performance, and the need for future replacement planning.

Key Facts

Inspection date: August 28, 2016
Report issued September 7, 2016
Twelve SEMCO True 3Å (TE‑56) wheels installed in 2000
Approximately 16 years of continuous 24/7 operation
Energy savings since 2007 exceeded $9,000,000 (≈ $600,000 per year)
Wheel revolutions estimated at 170,000,000
Supply airflow observed: 60,000 CFM
Exhaust airflow observed: 78,000 CFM
Measured sensible and latent effectiveness: 86%
More than 40 wheels across Johns Hopkins buildings operating 13–16 years

Challenge

Determine the current condition of the installed total energy wheels and assess whether maintenance funds should be allocated for repair or replacement.

Solution

A detailed inspection was conducted by FläktGroup SEMCO and Advanced Thermal Solutions personnel. Each wheel was slowed to minimum speed for evaluation of media integrity, plugging, corrosion, seals, bearings, casing, drives, sensors, and purge operation. Performance readings were compared to published specifications to validate continued effectiveness.

Results

Wheel media found tight and structurally intact with no gaps
No plugging observed; pressure loss aligned with published data
No corrosion detected due to effective protective coating
Cosmetic scarring noted on two wheels due to missing purge‑section screws
One drive belt required reconnection
Operational efficiency matched expected performance for a new wheel
Recommended average wheel lifespan estimated at 25 years with planned replacements