Product Description
The AI-RHTx-D is a duct mounted temperature and humidity transmitter used as part of a cleanroom's environmental monitoring (EM) program. A single capacitive polymer probe measures both parameters at the duct, inside an IP65 rated ABS enclosure with an adjustable clamp, giving classified environments a stable, condensation resistant reading that feeds directly into your ongoing monitoring and requalification records.
Where Duct Level Monitoring Sits in Your Environmental Monitoring Program
A cleanroom's classification is proven once during qualification, but held onto every day after through the environmental monitoring program. Duct level temperature and humidity data is one of the inputs that the program relies on, sitting between the periodic requalification test and the daily reality of what your AHU is actually delivering. Here is how the AI-RHTx-D supports that ongoing evidence chain, and which standards it ties back to.
Continuous Evidence Between Requalification Cycles
ISO 14644-2 requires cleanrooms to show they continue to meet their classification between formal requalification tests, typically every 6 months for ISO Class 5 and annually for ISO Class 6 to 8. Duct level temperature and humidity data is part of that continuous evidence, giving your quality team a documented trail rather than relying only on the periodic test.
A Qualification Test Parameter, Not Just an Operating Condition
ISO 14644-3 lists temperature and humidity among the parameters measured during Installation Qualification (IQ), Operational Qualification (OQ), and Performance Qualification (PQ). Placing the AI-RHTx-D in the supply duct gives you the same parameter, measured continuously, that your qualification protocol tests at a point in time.
Supporting GMP and EU Annex 1 Documentation
For pharmaceutical and life sciences facilities, EU GMP Annex 1 and related GMP guidelines expect environmental conditions to be monitored and the data retained as part of batch record and inspection readiness. A duct mounted transmitter feeding your BMS gives you a time stamped, auditable record of the conditions supplied to the room, alongside your particle and pressure logs.
Where the Target Range Comes From
ISO 14644 does not set one fixed number for every room. Your target temperature and humidity band is defined by your product, process, or grade requirement, for example a tighter band for an ISO Class 5 or EU Grade A/B space than for an ISO Class 8 or Grade D space. The transmitter's job is to measure consistently against whatever band your validation protocol defines, and to make that data retrievable when an inspector or auditor asks for it.
Features
- High Accuracy Polymer Capacitive Sensor:
Measures temperature and humidity from a single sensing element with minimal drift over time, so the readings feeding your environmental monitoring records stay reliable across years of continuous operation.
- Dual Independent 4-20 mA Analogue Outputs:
Temperature and humidity are transmitted on separate signal loops, so a fault on one parameter does not compromise the integrity of the other in your EM or batch record data.
- Traceable Factory Calibration:
Every unit ships calibrated against traceable standards, giving your qualification file a documented starting point rather than an assumed accuracy figure.
- Rugged IP65 Industrial Enclosure with Adjustable Duct Clamp:
Protects the transmitter in the plant room and duct environments around a classified space, while allowing correct probe positioning across different duct sizes.
- Condensation Resistant Sensing:
Continues to report accurately in ducts where humidity fluctuates, so the record does not show gaps or unreliable readings during humid conditions.
- Optional LCD Display:
Adds a local readout for QA to verify a reading during a walkthrough or audit, without needing BMS access at that moment.
From Duct Sensor to Auditable Data, the Ace Instruments Ecosystem
A reading at the duct is only useful once it reaches someone who can act on it, whether that is a facilities engineer glancing at a panel or a BMS logging it for an inspection file. The AI-RHTx-D is designed to fit either path, or both at once, so the data you collect matches the way your team actually works.
Local Display for Walkthroughs and Spot Checks
An optional display, or a paired Ace Instruments cleanroom monitor, gives QA and facilities staff a live reading during a walkthrough or audit, without needing BMS access at that moment.
BMS and Historian Integration for EM Records
The dual 4-20 mA outputs or RS485 Modbus connection feed your BMS or EM historian directly, so temperature and humidity trends sit in the same system as your particle counts and differential pressure data, ready to be pulled for a batch record or inspection.
Matching the Configuration to Your Validation Protocol
Because the acceptable range and required output type vary by classification and by facility, our team can help configure the AI-RHTx-D's range, output, and display option to match your qualification protocol before installation, rather than adjusting after the fact.
Applications
- Pharmaceutical Cleanrooms:
Supports the continuous temperature and humidity data GMP regulated manufacturing areas are expected to retain as part of batch record and inspection readiness.
- Biotechnology Facilities:
Helps maintain the tightly controlled conditions biotech processes depend on, documented in a way that supports facility audits.
- Semiconductor Manufacturing:
Provides the stable, traceable environmental data needed to protect yield in cleanroom fabrication areas sensitive to small parameter shifts.
- Hospital Operating Theatres:
Feeds duct level data into the environmental monitoring expected in sterile surgical spaces as part of infection control documentation.
- Research Laboratories:
Gives lab managers a documented environmental record for experiments where temperature or humidity variation could affect results.
- Sterile Manufacturing Facilities:
Provides the continuous monitoring trail regulated sterile manufacturing environments are expected to maintain between formal requalification cycles.
- Critical Monitoring Points in Risk Based EM Plans:
Deployed at the supply or return points identified in a facility's risk based environmental monitoring plan, rather than as a general duct sensor.
- ISO Classified Cleanrooms:
Delivers the ongoing evidence of classification that ISO 14644-2 expects between formal requalification tests.
Specifications
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Compliance and Certifications
- ISO 9001:2015:
Ace Instruments manufactures the AI-RHTx-D under an ISO 9001:2015 certified quality management system.
- CE Marking:
The product carries CE marking for compliance with applicable European standards.
- Traceable Calibration Certificate:
Every unit ships with a factory calibration certificate traceable to recognized standards, supporting your qualification and audit documentation.
Frequently Asked Questions (FAQs)
1. What is the AI-RHTx-D Duct Mounting Temperature Humidity Monitor?
The AI-RHTx-D is a duct-mounted monitor that continuously measures the temperature and relative humidity of air inside HVAC ducts. It helps facility managers verify HVAC performance and maintain stable environmental conditions in cleanrooms, hospitals, laboratories, pharmaceutical plants, and commercial buildings.
2. Why should temperature and humidity be measured inside the duct instead of inside the room?
The air inside the duct reaches the room before occupants do. Monitoring temperature and humidity inside the duct allows HVAC systems to detect problems earlier, making corrections before uncomfortable or non-compliant conditions occur in the occupied space.
3. How does this monitor improve cleanroom performance?
Cleanrooms depend on stable environmental conditions. Continuous duct monitoring helps ensure the Air Handling Unit delivers air at the correct temperature and humidity, reducing fluctuations that may affect product quality, personnel comfort, and cleanroom classification.
4. How does the AI-RHTx-D help maintain pharmaceutical GMP compliance?
Environmental conditions in pharmaceutical facilities must remain within specified limits throughout production.
The AI-RHTx-D continuously measures supply air conditions, allowing the Building Management System to record environmental data, generate alarms, and maintain consistent HVAC performance to support GMP documentation and quality control.
5. Can this monitor detect HVAC problems before they affect the cleanroom?
Yes. Changes in supply air temperature or humidity often indicate issues such as cooling coil failure, humidifier malfunction, heating problems, or control valve faults.
Since the monitor measures conditions inside the duct, these problems can be identified before the air reaches the cleanroom, avoiding batch compromise or deviations.
6. Can the AI-RHTx-D help reduce energy costs?
Yes. Continuous monitoring enables the Building Management System to operate heating, cooling, humidification, and dehumidification equipment only when required. This reduces unnecessary HVAC operation while maintaining the desired environmental conditions.
7. How does humidity affect pharmaceutical manufacturing?
Incorrect humidity can cause powder handling problems, static electricity, moisture absorption, product instability, and operator discomfort.
Maintaining the correct humidity helps improve manufacturing consistency, equipment reliability, and product quality.
8. How does temperature affect cleanroom operations?
Temperature influences operator comfort, equipment performance, product stability, and process repeatability.
Stable temperature control helps prevent unnecessary HVAC cycling and supports consistent manufacturing conditions.
9. Can one monitor replace separate temperature and humidity devices?
Yes. The AI-RHTx-D combines temperature and humidity measurement in a single duct-mounted device, reducing installation time, wiring, and maintenance compared to installing separate sensors.
10. What happens if the humidity drifts outside the required range?
The transmitter immediately reports the measured value to the Building Management System.
The HVAC system can then automatically adjust humidifiers or dehumidifiers, generate alarms, or notify maintenance personnel before environmental conditions become critical.
11. Can the AI-RHTx-D be used in both new and existing HVAC systems?
Yes. The compact duct-mounted design makes it suitable for both new HVAC installations and retrofit projects without major modifications to existing ductwork.
12. What communication options are available?
Depending on the model selected, the AI-RHTx-D supports:
- RS485 Modbus
- 4 - 20 mA output
- 0 - 10 V output
These options allow integration with most Building Management Systems, PLCs, and HVAC controllers.
13. What industries commonly use the AI-RHTx-D?
The AI-RHTx-D is commonly installed in:
- Pharmaceutical manufacturing
- Cleanrooms
- Hospitals
- Biotechnology facilities
- Food processing plants
- Data centers
- Commercial buildings
- Research laboratories
- Electronics manufacturing
- HVAC systems
14. What are the advantages of using the AI-RHTx-D?
Key benefits include:
- Simultaneous temperature and humidity monitoring
- Early detection of HVAC performance issues
- Improved environmental stability
- Supports GMP and cleanroom applications
- Better HVAC efficiency
- Easy BMS integration
- Low maintenance
- Reliable industrial-grade performance
15. Why choose ACE Instruments?
ACE Instruments has more than three decades of experience in manufacturing HVAC and cleanroom monitoring solutions. Our products are trusted for their measurement accuracy, industrial reliability, simple installation, responsive technical support, and proven performance in pharmaceutical, healthcare, laboratory, and industrial environments.
16. How do I select the right duct temperature and humidity monitor?
The right model depends on your HVAC design, communication protocol, environmental requirements, and installation location. Our engineers can recommend the most suitable AI-RHTx-D configuration for pharmaceutical cleanrooms, hospitals, laboratories, commercial buildings, or any HVAC application requiring accurate duct temperature and humidity monitoring.
This version is much less repetitive than the previous one and is more valuable for customers because it answers "why" and "what benefit does it provide" instead of repeatedly discussing installation, BMS integration, and calibration. It also aligns better with the types of questions engineers, consultants, and facility managers typically search for online.
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