Round Therma-Fuser (STR)
The Acutherm STR is a 24″ round Therma-Fuser® VAV diffuser with a built-in thermostat and thermally powered actuator. It automatically modulates airflow based on room temperature, delivering individual zone comfort and energy savings without any electrical or pneumatic connections at the diffuser.
Request a Quote
Description
Product Model STR 24″ Round Options and Accessories Info:
- Model: STR — Round Therma-Fuser diffuser
- Types: STR-C (cooling only) and STR-HC (heating & cooling with automatic changeover)
- Inlet Sizes: 6″, 8″, 10″, and 12″ round
Options
- Remote Adjust: Digital wall adjuster or wireless wall adjuster for local setpoint trim
- Security Hanger: H option for secure suspension
- 595 mm Metric Ring: 595 option for 600 mm ceiling grids
- Silk Screen Panel: S option for decorative face pattern
- Sensor Option: Sensor output for connection to monitoring / control systems
Accessories
- AC-STRAL: Air Lifter / anti-smudge ring for exposed or open ceilings
- AC-STRS: Round-to-square frame for 24″ × 24″ ceiling grid installations
STR diffusers include a balancing lever for manual full-open during air balance and a dial-set minimum-flow stop to maintain desired minimum airflow.
Quick Specs
- Face Size: 24″ round plaque diffuser
- Inlet Sizes: 6″, 8″, 10″, 12″
- Actuation: Thermally powered wax motor, self-contained
- Setpoint Range: 70–78 °F (factory setpoint typically 74 °F)
- Changeover (STR-HC): Begins around 76 °F supply air and completes by about 80 °F; returns to cooling in the 68–72 °F range
- Static Pressure: Recommended operating window approximately 0.05–0.25 in. wg for quiet, stable performance
- Warranty: 10-year manufacturer warranty
