TWIST-CUT

PART 1 – GENERAL

1.1 SUMMARY

A. Compact stamped swirl supply diffuser(s) providing a fixed 360° radial swirl diffusion pattern for rapid mixing; suitable for heating and cooling applications and VAV systems.

B. Unit construction includes an integral backpan with die-drawn collar (standard TWIST) or an integral insulated molded fiberglass back (CUT versions), as scheduled.

C. Ceiling integration: 24 in x 24 in lay-in face suitable for T-bar ceilings.

D. Optional insulation: R6 fiberglass insulation option available; insulation shall comply with ASTM E84 flame and smoke requirements.

E. Optional dampers: provide opposed blade damper (OBD) or radial sliding blade damper (RSBD) where scheduled.

1.2 SUBMITTALS

A. Product Data: Manufacturer’s data for scheduled model(s) and neck size(s), including airflow range, pressure loss, diffuser-generated NC, and published throw data.

B. Shop Drawings: Show scheduled model (TWIST / TWIST-CUT / TWIST-ALU / TWIST-ALU-CUT), face size (24 x 24), neck size (6/8/10/12), material/finish, insulation option (IR6/CUT), damper type (OBD/RSBD), and mounting details for T-bar lay-in.

C. Airflow Prediction Report (Required – SelectiV): Provide a manufacturer-generated SelectiV airflow prediction report for each diffuser type and each distinct room condition using manufacturer performance data and recognized airflow physics corrections. Report shall include:

1. 3D room model with diffuser locations
2. Predicted airflow visualization views: plan, section, elevation
3. Throws for terminal velocities of 150, 100, 60, 50, 40, 30, and 20 fpm
4. Pressure loss at scheduled airflow
5. Diffuser-generated NC at scheduled airflow
6. Perceived NC at room center (5 ft height) from all sources combined across 63–8000 Hz octave bands; include key assumptions used

D. Verified CFD Validation (When Indicated): Provide EffectiV Verified CFD validation and summary report for spaces indicated and/or when operation is outside published selection limits.

1.3 SUBSTITUTIONS

A. Substitutions per Division 01. Proposed equals shall provide a line-by-line compliance matrix including all Part 1 deliverables, including the SelectiV Airflow Prediction Report deliverables.

PART 2 – PRODUCTS

2.1 BASIS OF DESIGN

A. EffectiV TWIST compact stamped swirl diffuser with integral backpan.

2.2 MODELS (AS SCHEDULED)

A. TWIST: steel, integral backpan with die-drawn collar.

B. TWIST-CUT: steel, integral R6 molded fiberglass back, pre-scored to field-cut neck for 6 in through 12 in collars.

C. TWIST-ALU: aluminum, integral backpan with die-drawn collar.

D. TWIST-ALU-CUT: aluminum, integral R6 molded fiberglass back, pre-scored to field-cut neck for 6 in through 12 in collars.

2.3 SIZES AND PERFORMANCE (AS SCHEDULED)

A. Face: 24 in x 24 in.

B. Neck sizes: 6 in, 8 in, 10 in, 12 in.

C. Provide performance per published manufacturer data for scheduled neck size and airflow, including pressure loss, diffuser-generated NC, and throw values.

2.4 MATERIALS AND FINISH

A. Material: heavy-gauge galvanized steel or heavy-gauge aluminum, as scheduled.

B. Finish: factory powder coat, TGIC-free, white RAL 9016 unless otherwise scheduled.

2.5 INSULATION (AS SCHEDULED)

A. IR6 / CUT insulation: R6 molded fiberglass back, where scheduled; insulation to comply with ASTM E84 flame and smoke requirements.

2.6 DAMPERS (AS SCHEDULED)

A. Provide damper type as scheduled:

1. OBD opposed blade damper
2. RSBD radial sliding blade damper

PART 3 – EXECUTION

3.1 INSTALLATION

A. Install in T-bar ceiling lay-in configuration; ensure diffuser is level and seated properly.

B. For CUT versions, field-cut collar opening only within the pre-scored range for the scheduled neck size.

C. Install dampers where scheduled and provide access for balancing.

3.2 ADJUSTING

A. Balance to scheduled airflow.