VAV Safety Control Systems for Labs & Cleanrooms

Overview

Struggling with complex DDC coding or VAV valves that ignore pressure and IAQ? This decoupled solution delivers lab‑grade safety – without programming or lock‑in.

Traditional lab ventilation forces you to choose between over‑engineered DDC (costly, fragile) or limited VAV valves (no pressure, no IAQ).

Saswell’s vertical VAV solution changes that. It combines a built‑in ±500Pa DP sensor (0.1 Pa resolution), pressure‑independent PI control, native BACnet, and an optional laptop‑free HMI – all in one decoupled device. Plug‑and‑play for labs and cleanrooms, with zero programming and full supply chain freedom.

Key capabilities at a glance:

● ±0.1 Pa pressure resolution
● Built‑in ±500Pa DP sensor
● 0‑10V any‑actuator compatibility
● Native BACnet MS/TP & Modbus
● Laptop‑free on‑site tuning(optional HMI)

Traditional DDC vs decoupled VAV controller maintenance comparison illustration

Solution Architecture

At the heart of this solution is the HDC218-VAV controller with an onboard ±500Pa differential pressure sensor (0.1 Pa resolution). It reads room-to-corridor pressure and modulates any 0-10V actuator. The optional SAS965-HMI panel enables laptop-free on-site tuning. All control logic is pre-configured – zero programming required.

Complete VAV closed-loop control system diagram: HDC218-VAV controller, SAS965-HMI, 0-10V actuator, and BMS integration

Dimension	Standard Integrated Valve	Universal DDC System	Saswell Vertical Solution
Temp Control	✔ Supported	✔ Supported	✔ High-Precision PID
Pressure Control	✖ Not Supported	✔ Req. Extra Modules	✔ Built-in ±500Pa Sensor
Airflow Control	✖ Not Supported	✔ Req. Coding	✔ Real-time Flow Monitoring
IAQ/CO₂	✖ Not Supported	✔ Req. External Logic	✔ Direct 0-10V Sensor Sync
Usability	Low	High (Coding Skills Req.)	Low (HMI Menu-Driven)

How this architecture solves lab & cleanroom pain points

● Decoupled hardware: Replace only failed component, 43.5% lower TCO Learn how decoupled hardware lowers TCO by 43.5% →

● Pressure-independent logic: Dynamic compensation, prevents hunting, ensures safe negative pressure Learn how it eliminates hunting →

● Native BACnet MS/TP: Plug-and-play with any BMS, no gateway, no lock-in

🔗 Compare decoupled vs integrated VAV architectures →

Application Scenarios

Laboratories:Safety as the Bottom Line

Challenge: Labs must maintain a constant negative pressure (e.g., -15Pa) to prevent contaminant leakage, and provide adequate fresh air based on occupancy – but traditional VAV valves ignore pressure and CO₂.

Our solution: The HDC218-VAV uses an onboard ±500Pa DP sensor (0.1 Pa resolution) to directly monitor room‑to‑corridor pressure. It dynamically modulates the damper to keep the negative setpoint even when duct pressure fluctuates. At the same time, a connected CO₂ sensor triggers Demand Controlled Ventilation (DCV), automatically increasing fresh air when occupancy rises.

● Constant negative pressure – No external transmitter needed.
● Smart IAQ linkage – CO₂‑based DCV ensures researcher health.

How to prevent pressure‑related system hunting | CO₂‑based DCV Guide

Laboratory VAV system installation example: HDC218-VAV controller with pressure sensor and damper actuator

Cleanrooms & Theaters:
Precision Constant Volume for Critical Zones

Challenge: Cleanrooms and operating theaters require a constant air change rate to maintain ISO cleanliness. Filter clogging or duct pressure variations can cause airflow to drop, risking contamination.

Our solution: The HDC218-VAV offers one‑touch switching between CAV (Constant Air Volume) and VAV modes. In CAV mode, the algorithm locks the damper position regardless of upstream pressure changes – ensuring stable air changes. You can also set min/max flow thresholds; if a filter clog reduces airflow, the system triggers an immediate alarm.

● CAV/VAV one‑touch switching – Stable air change rates, ISO compliance.
● Threshold alarms – Instant alert for filter clog or abnormal airflow.

See how CAV mode works across different HVAC architectures →

Cleanroom VAV control: HDC218-VAV maintaining constant airflow and pressure with touchscreen HMI

Need a Solution for Commercial Buildings?

Reduce energy costs, break brand lock‑in, and achieve LEED/WELL with our open, decoupled VAV system. 1/3 the price of Tier‑1 brands, laptop‑free tuning,
and native BACnet integration.

Explore Commercial VAV Solution

Advantages

"Dashboard" Style Control

The SAS965-HMI displays Temperature, Pressure, Flow, and CO₂ at a glance. Administrators manage the room like a pilot in a cockpit — no laptop required for field commissioning.
Compatibility & Retrofit Savings

If your existing Siemens, Honeywell, or Belimo actuators support 0-10V, our controller can drive them directly. Reduce retrofit costs by over 50% by keeping your current ductwork and valves.
Power-Fail Memory

In critical environments, there is no room for error. The HDC218 automatically restores all safety setpoints after a power outage, ensuring your safety barrier remains intact.

Related Products

VAV Controller

HDC218-VAV

LEARN MORE

● Power Input: 100~240VAC / 50~60Hz
● Built-in Power Conversion Module: Provides 24V/1A for damper power supply
● Built-in Digital High-Precision Differential Pressure Sensor
● Supports BACnet MS/TP and Modbus Protocols
● 3 Analog Outputs (AO), 5 Digital Outputs (DO), 3 Digital or Analog Inputs
● Can be expanded with additional I/O via HDC-IO
● Applicable for VAV Box, Venturi Valve, Variable Air Volume Valve, Lab Fume Hood Control, etc.
● Dimensions: 121 x 113 x 47.3 (mm)

The ultimate universal VAV solution designed for high-performance velocity control and seamless BACnet integration.

HMI Control

SAS965-HMI

LEARN MORE

● Power Supply: 9~30VDC, DC Carrier Communication and Power Supply
● Display: 4-inch full capacitive touch color screen, resolution 480*480 dpi
● Temperature Display Range: 0~60°C, accuracy ±0.5°C
● Humidity Display Range: 10~99%, accuracy ±5%
● Interface: 2-wire DC carrier communication; external NTC sensor
● Optional Wi-Fi Function: Supports remote control via mobile app
● Dimensions: 86*86*11mm

Get In Touch

Contact our friendly Customer Service team for any Question,Concern, or Suggestion. We'd love to hear from you!

Headquater hotline: +86 755 61218391

Headquater email: info@saswell.com

MENA tech support hotline: +97155 6743682

MENA tech support email: support@saswell.com