Flexible Configurations
Choose from PM2.5, CO2, TVOC, temperature and humidity sensing combinations to match different HVAC control strategies.
A54 Series · HVAC IAQ Sensor Platform
HVAC Indoor Air Quality Sensors for Fresh-Air Units and AHU Systems
The A54 Series is a compact air quality sensing platform designed for HVAC equipment integration. Select the right combination of PM2.5, CO2, TVOC, temperature and humidity sensing for fresh-air units, AHU systems and smart ventilation control.
- Multiple sensing configurations in one compact platform
- RS485 communication for controller and HVAC equipment integration
- Designed for fresh-air systems, AHU equipment and indoor air quality control
Platform Overview
One Compact Sensor Platform for Different HVAC Requirements
From dedicated PM2.5 and CO2 sensing to a complete 5-in-1 IAQ configuration, the A54 Series helps HVAC equipment manufacturers select the right sensing combination without changing the overall integration approach.
Compact Integration
A unified enclosure concept simplifies mechanical integration across different HVAC equipment models.
RS485 Communication
Stable RS485 data output supports connection with fresh-air units, AHU controllers and distributed HVAC control systems.
Built for HVAC Applications
Suitable for indoor air quality monitoring, ventilation management, filtration monitoring and comfort-condition sensing.
HVAC Control Inputs
Turn Indoor Air Quality Data into Smarter HVAC Control
Modern ventilation systems need more than basic temperature sensing. By monitoring particulate matter, carbon dioxide, volatile organic compounds and comfort conditions, HVAC equipment can respond more intelligently to indoor air quality changes and support more effective ventilation management.
PM2.5Monitor airborne particles to support filtration-performance evaluation and indoor particle control.
CO2Use CO2 concentration as an input for ventilation adjustment and occupancy-related fresh-air control.
TVOCDetect changes in indoor volatile organic compounds and support responsive ventilation strategies.
Temperature & HumidityTrack indoor environmental conditions to support HVAC regulation and climate management.
How the A54 Series Works in HVAC Systems
The A54 Series continuously measures indoor air quality parameters and transmits sensor data through an RS485 interface. HVAC controllers can use the data to support ventilation adjustment, filtration monitoring and indoor air quality management strategies.
Detect
Indoor air passes through rooms, ducts or HVAC airflow paths.
Identify
A54 identifies PM2.5, CO2, TVOC, temperature and humidity data.
Transmit
Sensor data is sent through RS485 to the HVAC control system.
Adjust
HVAC equipment updates ventilation, filtration and IAQ logic.
A54 sensors provide measurement data inputs. Control actions are executed by the HVAC control system according to the configured strategy.
Choose the Right A54 Sensor for Your HVAC Application
From basic environmental monitoring to complete indoor air quality sensing, the A54 Series offers multiple configurations for different HVAC product requirements.
Flagship Model
A54-20 5-in-1 Air Quality Sensor
Complete IAQ sensing platform for fresh-air units, AHU systems and smart ventilation control.
- PM2.5
- CO2
- Temperature
- Humidity
- TVOC
- RS485
- Complete IAQ Monitoring
- Smart Ventilation
Balanced IAQ
A54-23 4-in-1 Air Quality Sensor
Balanced sensing configuration for particle monitoring, CO2-based ventilation and comfort-condition management.
- PM2.5
- CO2
- Temperature
- Humidity
- RS485
- Commercial HVAC
- Fresh-Air Units
- AHU Equipment
Compact Environmental
A54-22 3-in-1 Air Quality Sensor
Efficient environmental sensing for particulate monitoring and indoor comfort-condition management.
- PM2.5
- Temperature
- Humidity
- RS485
- Ventilation Systems
- Filtration Monitoring
- Indoor Air Quality Equipment
Dedicated PM2.5
A54-21 PM2.5 Sensor
Dedicated particulate sensing node for ventilation cleanliness and indoor air quality monitoring.
- PM2.5
- Laser Scattering Measurement
- RS485
- Particle Monitoring
- Filter-Performance Evaluation
- Fresh-Air Equipment
Dedicated CO2
A54-24 CO2 Sensor
Dedicated NDIR CO2 sensing solution for demand-controlled ventilation and HVAC air quality management.
- CO2
- NDIR Infrared Sensing
- RS485
- Demand-Controlled Ventilation
- Fresh-Air Units
- AHU Systems
Comfort Conditions
A54-25 Temperature and Humidity Sensor
Compact comfort-condition sensor for HVAC environmental monitoring applications.
- Temperature
- Humidity
- CMOS-Based Temperature and Humidity Measurement
- RS485
- Climate Monitoring
- Ventilation Equipment
Compare A54 Series HVAC Air Quality Sensors
Compare sensing parameters and application positioning to select the most suitable A54 configuration for your HVAC equipment.
| Model | PM2.5 | CO2 | TVOC | Temperature | Humidity | RS485 | Recommended Use |
|---|---|---|---|---|---|---|---|
| A54-20 | Yes | Yes | Yes | Yes | Yes | Yes | Complete HVAC IAQ monitoring |
| A54-23 | Yes | Yes | - | Yes | Yes | Yes | Fresh-air and AHU control |
| A54-22 | Yes | - | - | Yes | Yes | Yes | Particle and comfort monitoring |
| A54-21 | Yes | - | - | - | - | Yes | Dedicated PM2.5 monitoring |
| A54-24 | - | Yes | - | - | - | Yes | CO2-based ventilation control |
| A54-25 | - | - | - | Yes | Yes | Yes | Basic environmental sensing |
Designed for HVAC Equipment Integration
Select a sensing configuration based on the type of HVAC equipment and the required indoor air quality strategy.
Fresh-Air Units
Monitor indoor particle concentration, CO2 levels and comfort conditions to support intelligent fresh-air management.
Recommended: A54-20 · A54-23 · A54-24
Air Handling Units
Provide air quality data inputs for AHU controllers and building ventilation strategies.
Recommended: A54-20 · A54-23 · A54-22
Heat-Recovery Ventilation Systems
Integrate compact sensing nodes into ventilation equipment for continuous environmental monitoring.
Recommended: A54-20 · A54-22 · A54-25
Filtration and IAQ Equipment
Monitor airborne particles and environmental conditions to support filtration-performance evaluation and indoor air quality management.
Recommended: A54-21 · A54-22 · A54-20
Flagship Model
A54-20: Complete 5-in-1 Sensing for Advanced HVAC Systems
For HVAC systems that require a more complete indoor air quality picture, the A54-20 integrates PM2.5, CO2, TVOC, temperature and humidity sensing in one compact enclosure. It is suitable for fresh-air units, AHU systems and smart ventilation equipment that need multiple environmental data inputs from a single sensor node.
- PM2.5
- CO2
- TVOC
- Temperature
- Humidity
- 5-in-1 IAQ sensing in one compact module
- PM2.5, CO2, TVOC, temperature and humidity monitoring
- RS485 communication for HVAC controller integration
- Suitable for advanced fresh-air and air-handling equipment
Built for HVAC Product Development
The A54 Series is designed to help HVAC equipment manufacturers build scalable sensing solutions across different product tiers and application requirements.
01
Unified Mechanical Design
Multiple sensing configurations share a consistent enclosure concept, simplifying integration across different HVAC equipment models.
02
Scalable Sensor Configurations
Start with a dedicated PM2.5 or CO2 sensor, or select a multi-in-one IAQ node for more advanced HVAC systems.
03
Reliable Digital Communication
RS485 output supports stable data transmission and straightforward connection to HVAC control architectures.
04
Simplified Product Integration
A compact sensing platform helps equipment manufacturers streamline product planning and reduce repeated integration work.
Frequently Asked Questions About HVAC Air Quality Sensors
An HVAC indoor air quality sensor can measure one or more environmental parameters, such as PM2.5, CO2, TVOC, temperature and humidity. The required configuration depends on the ventilation strategy and the type of HVAC equipment.
The A54-20 is the most complete model in the A54 Series. It combines PM2.5, CO2, TVOC, temperature and humidity sensing in one compact module.
For CO2-based ventilation strategies, the A54-24 provides dedicated CO2 sensing. For systems that also require PM2.5 and comfort-condition monitoring, the A54-23 or A54-20 may be more suitable.
Yes. The A54 Series is designed for HVAC equipment integration, including fresh-air units, air-handling units and smart ventilation systems.
The A54 Series supports RS485 communication for integration with HVAC controllers and equipment control systems.
The A54-21 is a dedicated PM2.5 sensor. For applications that also require temperature and humidity monitoring, the A54-22 is a suitable option.
A multi-in-one sensor combines several environmental parameters in a compact enclosure. This can simplify equipment integration and provide HVAC controllers with a broader set of indoor air quality data.
Start by identifying the required sensing parameters and the HVAC control strategy. For basic particle monitoring, select A54-21. For CO2-based ventilation, select A54-24. For a complete IAQ solution, select A54-20.
Learn More About HVAC Indoor Air Quality Sensing
Explore practical resources for selecting air quality sensors and designing HVAC indoor air quality monitoring strategies.
HVAC and IAQ
Air Quality Monitoring Solution for HVAC Applications
Explore how air sensors integrated into 86 controllers enable room-level air quality monitoring, HVAC linkage, fresh-air coordination and closed-loop control.
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Multi-in-One Sensors
Multi-in-One Air Quality Module System Design
Learn how multi-in-one air quality modules handle integration, selection, system connection and calibration for HVAC and commercial air monitoring.
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Sensor Technology
What Is the Difference Between NDIR and MOS Sensors?
Compare NDIR and MOS sensors across sensing principles, selectivity, stability, CO2 measurement, VOC interpretation and air quality applications.
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CO2 Sensing
How Does a CO2 Sensor Work?
Understand how CO2 sensors use NDIR infrared absorption to measure concentration and support HVAC, fresh-air and environmental monitoring.
Read ArticleFind the Right Air Quality Sensor for Your HVAC Project
Share your sensing parameters, HVAC control strategy, installation position and communication requirements. Our engineering team will recommend a suitable A54 sensor configuration for your HVAC equipment platform.