HVAC Equipment Map — B3 Yellow Zone

Date: 2026-03-04 | Version: v01 ACTIVE | Author: Claude (Opus 4.6)

Source Files

File	Location	Size	Layers
HVAC Drawing	`Source/2026-03-04_v01_HVAC-All-Floors.dxf`	39 MB	151 total, 33 HVAC-related
Furniture Layout	`Source/2026-03-04_Furniture-Layout-Original-AutoCAD.dxf`	7.7 MB	40 total, 0 HVAC

CRITICAL: The furniture layout DXF contains ZERO HVAC layers. All HVAC data is exclusively in the dedicated HVAC DXF.

Coordinate System Note

The two DXFs use different coordinate systems:

Furniture DXF: Meters (~42-79 X range, ~14-32 Y range)
HVAC DXF: Millimeters (~245,000-300,000 X range, ~261,000-278,000 Y range)

Cross-referencing relies on the B3 floor reference block FRU-B-3 at X: 263,875 | Y: 275,215 (HVAC DXF).

HVAC Layers Identified (33 layers)

Ductwork Layers

Layer	Description
`MECH-Supply Duct`	Main supply air ductwork
`MECH-RETURN DUCT`	Main return air ductwork
`MECH-BRANCH`	Branch duct connections
`MECH-EXHAUST DUCT`	Exhaust air ducts
`MECH-FRISH DUCT`	Fresh air intake ducts
`ME S.A DUCT`	Supply air duct (alternate naming)
`ME R.A Duct`	Return air duct (alternate naming)
`Supply Air Duct`	Supply air duct (third naming variant)
`Duct` / `Duct R`	Generic duct layers
`H-DUCT`	Additional duct layer

Equipment Layers

Layer	Description
`MECH-Indoor unit`	VRF indoor fan coil units (CRITICAL)
`MECH-Indoor unit-duct`	Connection ducts to indoor units
`MECH-Outdoor unit`	Outdoor condenser units
`MECH-AHU`	Air Handling Units
`MECH-FAN`	Fan components
`MECH-VD`	Volume Dampers

Distribution Layers

Layer	Description
`MECH-Blenum Box Supply`	Plenum boxes (note: "Blenum" is DXF typo)
`VI-AIR DEVICES`	Diffusers, grilles, air terminals
`FLEXIBLE-DUCT` / `H-FLEXIBLE`	Flexible ductwork
`MECH-Flex joint`	Flexible connections

Piping Layers

Layer	Description
`MECH - Refrigerant Pipes`	Main refrigerant piping
`MECH-Refrigerant Branches`	Refrigerant branch lines
`MECH-Pip`	General piping

Annotation Layers

Layer	Description
`MECH-Text`	HVAC text annotations
`MECH-Space Taged`	Mechanical space tags
`MECH_ supply duct` / `MECH_flex`	Variant naming layers

Indoor Units Near B3 Yellow Zone

Reference: B3 floor marker at X: 263,875 | Y: 275,215

Primary Units (< 7,000 unit radius — likely serving B3 zone)

Unit	Block	X	Y	Dist. from B3 Ref	Notes
1	*U370	260,783	271,311	~4,980	Closest unit
2	*U371	260,783	271,311	~4,980	Paired with U370 (same position)
3	*U328	268,410	278,312	~5,492	NE quadrant
4	*U380	257,582	273,611	~6,494	West side

Secondary Units (7,000–20,000 radius — adjacent zones or shared)

Unit	Block	X	Y	Dist. from B3 Ref
5	*U372	253,795	261,985	~16,632
6	*U377	253,795	261,985	~16,632
7	*U378	253,795	261,985	~16,632
8	*U379	253,070	262,078	~17,010
9	*U131	280,734	268,434	~18,172
10	*U104	282,174	269,793	~19,085

Air Devices (Diffusers/Grilles) Near B3

VI-AIR DEVICES Layer — B3 Area

Block	X	Y	Dist. from B3 Ref	Rotation
A$C2c00dd91	252,428	274,072	~11,504	—
A$C2c00dd91	249,780	274,421	~14,117	270°
A$C2c00dd91	249,780	273,376	~14,214	270°
A$C2c00dd91	248,776	274,421	~15,120	270°
A$C2c00dd91	248,776	273,376	~15,211	270°
A$C2c00dd91	246,104	274,073	~17,808	—

Scale factors: 25.05 (standard diffusers) and 37.58 (VCD devices)
Color: 10 (cyan)

Implications for Acoustic Design

1. "Work With What We Have" Strategy

Based on the DXF analysis, the existing HVAC installation includes:

2–4 indoor VRF units serving the B3 yellow zone area
6+ air devices (linear slot diffusers/grilles) distributed across the zone
Duct runs on MECH-Supply Duct and MECH-RETURN DUCT layers

2. Last-Mile Modification Plan (Confirmed Approach)

Per the HVAC coordination log, the agreed strategy is:

[KEEP AS-IS]                    [MODIFY - LAST MILE ONLY]

Main VRF piping ──────────┐
Main supply/return ducts ─┤
Branch ducts to zone ─────┤
                          │
Indoor unit position ─────┤     ← Move to corridor/editing (non-critical zone)
                          │
                          ├──── Oversize final drops (increase duct diameter)
                          ├──── Insert inline acoustic silencers (baffle boxes)
                          ├──── Transition: hard pipe → flexible acoustic duct
                          ├──── S-curve routing (break line-of-sight)
                          ├──── Expanded acoustic plenum boxes
                          └──── Oversized diffusers (target ≤ 1.5 m/s)

3. Plenum Box Sizing Requirements

Target: Terminal air velocity ≤ 1.5 m/s at diffuser face

Typical VRF indoor unit airflow: 400–800 CFM (190–380 L/s) per unit

Required Face Area	At 1.5 m/s	At 2.0 m/s (relaxed)
400 CFM (190 L/s)	0.127 m² (36×36 cm)	0.095 m² (31×31 cm)
600 CFM (285 L/s)	0.190 m² (44×44 cm)	0.143 m² (38×38 cm)
800 CFM (380 L/s)	0.253 m² (50×50 cm)	0.190 m² (44×44 cm)

Standard commercial diffusers: Typically 2.5–4 m/s → we need ~2.5× the face area

4. Silencer Space Constraint

Available ceiling space: 60 cm (drop ceiling zone)

Typical rectangular silencers for VRF duct sizes:

200×200 mm duct: Silencer 300×300×600 mm (L) — FITS in 60 cm
250×250 mm duct: Silencer 350×350×900 mm (L) — FITS in 60 cm (tight)
300×300 mm duct: Silencer 400×400×1200 mm (L) — DOES NOT FIT vertically

Recommendation: Keep duct sizes ≤ 250 mm in the ceiling zone, or use horizontal-run silencers that fit within 60 cm height.

5. NC Budget Per Duct Run

For NC-15 total in VO room, HVAC contribution must be NC-10 to NC-12:

Component	Target NC	Achieved By
Supply duct to VO room	NC-10	2× inline silencers + plenum box
Return duct from VO room	NC-10	1× inline silencer + plenum box
Supply duct to Control room	NC-20	1× inline silencer
Indoor unit radiated noise	NC-10	Unit located outside critical rooms
Diffuser self-noise	NC-10	Oversized face area (≤ 1.5 m/s)
Duct breakout noise	NC-15	Lined ductwork (25 mm acoustic lining)

Outstanding Actions (From HVAC Coordination Log)

HVAC team to receive updated floor plan (from Sarah)
HVAC team to confirm assigned airflow (CFM/L/s) for MediaVerse area
HVAC team to confirm silencer fitment in 60 cm ceiling space
HVAC team to confirm indoor unit mounting method
HVAC team to confirm if branch routing can stay in east corridor
Need Daikin model numbers for indoor units to get noise data sheets
Need duct sizes from HVAC drawings to size silencers

This document should be updated when HVAC team provides floor plan review and airflow data.