SSOT — HVAC (B3 Yellow Zone)

Status: LOCKED 2026-03-05 | Source: B3-Existing.pdf (HVAC Contractor Drawing) | Cross-ref: SSOT-GEOMETRY.md (Zone Geometry)

THIS FILE IS THE SINGLE SOURCE OF TRUTH (SSOT) FOR ALL HVAC DATA.
All layout designs MUST respect these values. Indoor unit positions, ductwork, and refrigerant routing are EXISTING INFRASTRUCTURE that can only be modified through the agreed "last-mile" approach with the HVAC contractor.

SUPERSEDES: U380 position from DXF extraction (was approximate, now corrected by contractor drawing).

1. Source Document

Property	Value
File	`B3-Existing.pdf`
Type	HVAC Contractor Installation Drawing — As-Designed
System	Daikin VRF (Variable Refrigerant Flow)
Coverage	B3 Yellow Zone + adjacent areas (server room, corridors)
Date Received	2026-03-05

POSITION CONFIDENCE: Equipment specifications (TR, CFM, m³/h) are EXACT — read directly from drawing labels. Physical positions within the zone are APPROXIMATE — estimated from PDF visual analysis. For final construction, request exact coordinates from HVAC contractor's AutoCAD source file.

2. Indoor Units Inside Zone

Unit	Capacity	Airflow	Fresh Air	Return Air	Position (zone cm)	Confidence
B3-VRF-IDU-03	1.0 TR (3.52 kW)	318 CFM (150 L/s)	FA-10	RA-200	~(310, 225)	APPROX
B3-VRF-IDU-04	1.0 TR (3.52 kW)	318 CFM (150 L/s)	FA-58	RA-260	~(250, 75)	APPROX

Capacity Summary

Parameter	Value
Total cooling capacity	2.0 TR (7.04 kW) EXACT
Total airflow	636 CFM (300 L/s) EXACT
Units	2 × ceiling-mounted VRF cassettes
Cooling per m²	7,040 / 34.42 = 205 W/m²

CAPACITY CHECK: 205 W/m² provides adequate headroom for studio use with:

Video lighting rigs (~500-2000W)
Multiple computers + monitors (~300-600W)
Body heat from talent + crew (75W × 4 people = 300W)

Estimated studio heat load: ~200-250 W/m². Upgraded 2.0 TR system provides cooling capacity of 205 W/m² (7,040 W / 34.42 m²). IDU upgrade from 0.75 TR to 1.0 TR per unit — same fan speed (318 CFM), same ductwork, extra cooling via higher refrigerant flow.

Previous DXF Data — SUPERSEDED

The DXF extraction report identified U380 at zone position (688, 50) — near the SE corner. The B3-Existing PDF shows IDU-03 and IDU-04 in the CENTER-WEST area. The PDF is the HVAC contractor's design drawing and SUPERSEDES the DXF extraction for unit positions.

U380 mapping: U380 likely corresponds to one of IDU-03/IDU-04 (different naming conventions between architect DXF and HVAC contractor drawing). The DXF block position was either a placeholder or referenced a different revision.

3. Air Devices (Diffusers)

Type	Rating	Qty Inside Zone	Approx Positions	Confidence
AVD-09	540 m³/h each	3	Spread along E-W duct run, center area: ~(330, 190), ~(390, 160), ~(450, 130)	APPROX

Total diffuser capacity: 3 × 540 = 1,620 m³/h EXACT

4. Ductwork

Main Duct Runs

Duct	Size (mm)	Routing	Approx Y Position	Confidence
Main supply duct	300 × 200	E-W through center of zone, along column line	Y ≈ 140-200 cm from south	APPROX
Branch ducts	Smaller (est. 200 × 150)	From main duct to AVD-09 diffusers	Various	APPROX

DUCT BAND RULE: The main ductwork occupies a horizontal band from Y≈110 to Y≈230 (roughly aligned with the structural column line at Y=111-161). Any partition wall running N-S through this band will CROSS the ductwork and require acoustic penetration treatment.

Supply/Return Flow Bars (North Wall)

Type	Spec	Position	Approx X Range (zone cm)
S.FLOW BAR (Supply)	2 slots, 50mm wide, L=1.5m, 2 FLEXIBLE 150mm+VD	North wall, NW portion	X ≈ -80 → 70 (diagonal area)
S.FLOW BAR (Supply)	2 slots, 50mm wide, L=1.0m	North wall, left of center	X ≈ 70 → 170
R.FLOW BAR (Return)	2 slots, 50mm wide, L=1.5m	North wall, center-east portion	X ≈ 400 → 550
R.FLOW BAR (Return)	2 slots, 50mm wide, L=1.0m	West/diagonal wall area	Y ≈ 250-350 (on diagonal)

NORTH WALL SPLIT RULE: The north wall HVAC distribution splits at approximately X ≈ 396 cm (verified: 5191mm from NW corner = X = -123 + 519.1 = 396.1 cm).
West of X≈396: Supply bars (feed air INTO zone) — serves the NW area
East of X≈396: Return bars (extract air FROM zone) — serves the NE area
Dimension verification: 5191 + 3410 = 8601 = 8600mm (north wall) -- OK

5. Refrigerant Piping

Line	Size	Routing	Confidence
Liquid line	1/2" (12.7mm)	Along south wall, E-W	EXACT (from label)
Gas line	5/8" (15.9mm)	Along south wall, E-W	EXACT (from label)
Branch liquid	1/4" (6.35mm)	From south wall up to indoor units	EXACT (from label)
Branch gas	3/8" (9.53mm)	From south wall up to indoor units	EXACT (from label)

Identification: Lines marked "102F" in drawing

REFRIGERANT ROUTING RULE: Main refrigerant lines run along the SOUTH WALL at floor/ceiling level. Branch lines rise from the south wall to reach the indoor units. Any partition wall crossing the south wall area must provide rubber-grommeted penetrations for refrigerant lines, with vibration isolation clips every 60cm.

6. Adjacent HVAC (Outside Zone — Context Only)

Unit/Device	Spec	Location	Relevance to Zone
B3-Split-IDU-16	2.0 TR, 647 CFM	NE of zone — ROOM-SERVER	NOISE SOURCE: Server room HVAC generates noise that transmits through east wall
AUD-24	1,000 m³/h	NE of zone	Air noise through east wall
AUD-36	2,100 m³/h	East of zone — ROOM-SERVER	High-volume air movement = noise source
AVD-24	840 m³/h	SE of zone	Possible flanking through south/east corner

SERVER ROOM HVAC NOISE: B313 has 2.0 TR split unit + 2,100 m³/h air device + 1,000 m³/h air device. This is a significant noise source (estimated 55-65 dB(A)) adjacent to our east wall. The east wall STC rating must account for this combined HVAC + server equipment noise.

7. HVAC-to-Zone Position Map

8. Locked Rules for Layout Design

RULE 1 — UNIT CONSERVATION
The zone has exactly 2 indoor units (IDU-03, IDU-04) totaling 2.0 TR / 636 CFM. IDUs upgraded from 0.75 to 1.0 TR each (same fan speed, same ductwork). Layouts must distribute this capacity across all rooms.

RULE 2 — DUCT BAND CONSTRAINT
Main ductwork runs E-W through the zone at Y ≈ 110-230 cm (column line band). Any N-S partition wall crossing this band requires:

Acoustic duct boot at each penetration
Flex connection (min 30cm) on both sides of wall
Inline silencer (min 600mm long) on the quiet-room side
Fire damper per code
Each penetration degrades wall STC by 2-5 points unless properly treated

RULE 3 — NORTH WALL DISTRIBUTION SPLIT
The north wall HVAC splits at X ≈ 396 cm:

West of X=396: Supply flow bars (2.5m total length)
East of X=396: Return flow bars (1.5m total length)

Any room in the NW area can leverage existing supply bars for supplemental air supply. Rooms in the NE area can use existing return bars.

RULE 4 — REFRIGERANT ROUTING
Main refrigerant lines run along the south wall. Branch lines rise vertically to indoor units. Relocating an indoor unit:

Lateral shift ≤ 1m: extend branch lines (moderate cost, ~$200-500)
Lateral shift 1-2m: reroute branches (significant cost, ~$500-1500)
Lateral shift > 2m: requires HVAC contractor redesign

RULE 5 — NC COMPLIANCE PATH
Indoor units generate 25-40 dB(A) at 1m (depending on fan speed). For NC compliance:

Room NC Target	Unit Placement Requirement	Duct Treatment
NC-20 (VO)	Unit MUST be OUTSIDE the room	2× silencers + plenum + flex S-curve + oversized diffuser (≤1.5 m/s)
NC-25 (Control)	Unit MUST be OUTSIDE the room	1× silencer + plenum + flex
NC-30 (Studio)	Unit in adjacent space (editing/corridor)	1× silencer + lined duct
NC-35 (Editing)	Unit can be above (in ceiling plenum)	Basic silencer + flex connection

RULE 6 — UNIT SPATIAL BIAS
Both indoor units are in the WEST-CENTER of the zone (X ≈ 250-310). This creates a spatial bias:

E-W partition at X ≈ 250-300: Naturally splits units (one per side) — OPTIMAL
E-W partition at X < 220: Both units on east/studio side — audio rooms get NO direct HVAC
N-S partition at Y ≈ 250-300: Both units south of wall — parallel to duct run, no crossings

RULE 7 — SILENCER SPACE CONSTRAINT
Available ceiling plenum: 60 cm (slab at 350cm, acoustic ceiling at 275cm above float floor). Silencer sizing:

200×200mm duct → 300×300×600mm silencer — FITS
250×250mm duct → 350×350×900mm silencer — FITS (tight)
300×300mm duct → 400×400×1200mm silencer — DOES NOT FIT vertically

Keep duct sizes ≤ 250mm in the ceiling zone, or use horizontal-run silencers.

9. Quick Reference Block

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  SSOT-HVAC — LOCKED VALUES (2026-03-05)
═══════════════════════════════════════════════════════

INDOOR UNITS:
  IDU-03: 1.0 TR, 318 CFM, FA-10, RA-200  ~(310, 225)
  IDU-04: 1.0 TR, 318 CFM, FA-58, RA-260  ~(250, 75)
  Total:  2.0 TR (7.04 kW), 636 CFM

DIFFUSERS:
  3× AVD-09 @ 540 m³/h = 1,620 m³/h total

DUCTWORK:
  Main: 300×200mm, E-W run at Y≈140-200
  Duct band: Y ≈ 110–230 (column line zone)

NORTH WALL DISTRIBUTION:
  Supply zone: NW to X≈396 (bars total 2.5m)
  Return zone: X≈396 to NE (bar 1.5m)

REFRIGERANT:
  Main: ½" liquid + ⅝" gas along SOUTH WALL
  Branch: ¼" liquid + ⅜" gas rising to units
  ID: "102F"

ADJACENT NOISE (B313 Server Room):
  IDU-16: 2.0 TR + AUD-36: 2,100 m³/h
  Combined: 55–65 dB(A) through east wall

CEILING PLENUM: 60 cm (silencer max: 250mm duct)
COOLING DENSITY: 205 W/m² (7,040 W / 34.42 m²)

UNIT SPATIAL BIAS: WEST-CENTER (X≈250-310)
  Optimal partition: X ≈ 250–300 (splits units)
  Worst partition:   X < 220 (all HVAC on east side)

═══════════════════════════════════════════════════════
  Source: B3-Existing.pdf | Supersedes: DXF U380 data
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10. Reconciliation with SSOT-GEOMETRY

Parameter	SSOT-GEOMETRY	SSOT-HVAC	Status
Zone area	34.42 m²	(uses same)	CONSISTENT
Column positions	COL-W (364,136), COL-E (757,133)	Duct band aligns with column line	CONSISTENT
East wall	X=737, 10cm gypsum to B313	B313 has 2.0 TR unit = noise source	CONSISTENT
VRF unit position	"U380 near SE corner"	IDU-03 ~(310,225), IDU-04 ~(250,75)	SUPERSEDED -- PDF is authoritative
Ceiling space	Slab 350cm, effective 275cm	60cm plenum for silencers	CONSISTENT (350-15-60=275)
HVAC system	Daikin VRF	Daikin VRF confirmed (IDU-03, IDU-04)	CONSISTENT

ACTION REQUIRED: Update SSOT-GEOMETRY.md Section "Key Project Parameters" to reference IDU-03 and IDU-04 instead of "U380 near SE corner." The geometry values remain unchanged — only the HVAC unit reference needs updating to match this SSOT.

11. Authoritative Files

This file: SSOT-HVAC.html — Single Source of Truth for HVAC
Source drawing: B3-Existing.pdf (HVAC contractor as-designed)
Cross-reference: SSOT-GEOMETRY.md (zone dimensions, column positions)
Previous data: HVAC/2026-03-04_v01_HVAC-Equipment-Map.html (DXF extraction — SUPERSEDED for unit positions)
HVAC coordination: HVAC/2026-03-04_v01_HVAC-Coordination-Log.html