145X115X30 trapezoid shape underfloor fresh air flat duct system

This product is 145X115X30 （trapezoid shape) underfloor fresh air flat duct full fitting series, PVC 2.0mm thick modular duct components designed exclusively for ground-supply mechanical ventilation (MVHR/ERV) systems. The complete lineup includes straight couplers, 45°/90° horizontal/wall climb elbows, air volume dampers, tees, reducers, flat-to-round adapters, and multi-port T-type air distribution manifolds (4/5/7/8 branches ABS & metal variants) to assemble full underfloor ventilation duct networks.

Key Problems It Solves

1. Low ceiling height limitation: Traditional round 110/150mm ducts require thick ceiling screeds; the 30mm ultra-flat profile fits within thin floor leveling layers without raising finished floor height or cutting structural beams.
2. Complex directional routing barriers: Pre-made 45°/90° horizontal and wall-climb elbows eliminate custom on-site cutting, reducing airflow resistance and air leakage around wall corners, cabinetry, and structural studs.
3. Uneven room airflow distribution: T-type split manifolds evenly distribute fresh air to multiple bedrooms/living zones, while built-in dampers allow independent airflow balancing per branch to eliminate hot/cold spots.
4. Mismatched round fan & flat duct transitions: Φ110/Φ150 flat-to-round adapters seamlessly connect circular MVHR unit outlets to flat underfloor ducts without turbulent airflow pressure loss.
5. On-site assembly waste & slow installation: Standardized modular snap-fit ABS fittings cut construction labor time by 30% vs custom fabricated metal ductwork, with fully compatible 14511530mm 2.0-wall flat main tubes.

Product Information

Product Core Features

1. Ultra-low-profile 30mm thin design: Fits shallow floor screeds, avoids beam drilling and raised flooring renovation costs
2. 2.0mm thick reinforced pipe wall: High ring stiffness, anti-compression under floor cement, no pipe collapse after long-term floor covering load
3. Full modular matching series: One brand supplies all elbows, split manifolds, dampers and transition adapters, zero compatibility mismatch
4. Smooth inner ABS/PVC wall: Low air flow resistance, reduces MVHR fan power consumption and running noise
5. Adjustable airflow control: Dedicated volume dampers for independent zone air balancing across bedrooms, living areas
6. Dual flat-to-round conversion adapters (Φ110/Φ150): Universal connection to mainstream heat recovery ventilation units
7. Multi-port T-type distribution manifolds: 4/5/7/8 branch options for small apartments to large villas, uniform air splitting without airflow dead zones
8. Snap-fit assembly structure: Tool-free connection, tight sealing joints to prevent air leakage and dust intrusion inside ductwork
9. Moisture & corrosion resistant ABS material: No rust, mold resistance for long service life in underfloor damp environments
10. Lightweight construction: 70% lighter than galvanized metal duct fittings, lower transportation and installation labor cost

Application Scenarios

1. New-build small/mid-size residential apartments (90–130㎡): Home HVAC installers need complete underfloor fresh air duct kits to deliver ground-level clean air to each room without high ceiling drop; Zhongying full fitting set covers all routing and distribution needs for single-family apartments.
2. Low-ceiling old house renovation (apartment/loft with <2.6m ceiling height): Renovation contractors cannot install thick round ceiling ducts; 30mm flat duct + Zhongying wall climb elbows route ventilation under thin floor leveling without raising finished floors.
3. Large villa MVHR ground supply ventilation projects: HVAC engineering firms require multi-branch air manifolds to split fresh air to 6+ bedrooms; Zhongying 7/8-port ABS/metal T-manifolds provide balanced airflow across multi-story villa zones.
4. Office open-plan raised floor ventilation systems: Commercial MEP engineers install under-floor air supply for open workspaces; standardized Zhongying elbows and couplers simplify uniform duct layout across partitioned office zones.
5. Indoor air quality upgrade projects for allergy-prone family homes: HVAC technicians install balanced ground-supply fresh air to avoid ceiling draft discomfort; built-in Zhongying airflow dampers fine-tune air volume for children’s rooms, study rooms and master bedrooms separately.

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