Client: College of Charleston
Location: Downtown Charleston, SC
Year Completed: 2025
Services: Commercial water heater installation, gas line repiping, water supply repiping, roof venting, after-hours work
Client Type: Higher Education / Sports & Entertainment Venue
Challenge
TD Arena’s existing water heating system — a 260,000 BTU Raypak boiler with approximately 335 gallons of storage — struggled to meet the simultaneous high-volume hot water demands of four concession stands (each with a 3-compartment sink, lavatory faucets, and mop sink) plus two commercial washing machines. The aging system also presented venting concerns and was reaching the end of service life. Any disruption to arena operations during active events was not an option.
Solution
PlumbX engineered a full water heating system replacement using two Rinnai Commercial Hybrid Water Heating System Demand Duo units (Model CHS199100Hi). We removed the old Raypak boiler and storage tank, isolated the existing recirculation and gas supply, and installed the new dual-unit system. All water supply and gas lines were repiped and reconnected, and both units were vented directly to the roof via 2″ PVC sleeved through the existing metal piping to prevent backdrafts. Condensation lines with neutralizers were installed on each unit. Safety protocols included mechanical fume extraction, on-site fire blankets and extinguishers, and disarming nearby fire alarm zones during demolition — which was performed after hours over two nights to eliminate any impact on the venue.
Results
The new system delivers 398,000 combined BTUs with 240 gallons of total storage — a 53% increase in heating capacity. Both units tested with zero leaks and were confirmed fully operational, providing consistent hot water throughout the building to all concession and laundry points. The hybrid tankless/tank design provides faster recovery and better performance during peak-demand events while reducing the overall equipment footprint.
