HF3 Humidity and Temperature Transmitter
Rotronic HygroFlex3 HF3 Series – Wall, Duct & Space Mount Humidity & Temperature Transmitters
Advanced HVAC transmitter series with AirChip3000 technology, high accuracy (<2% RH / 0.3 K), auto-diagnostics, dew/frost point calculation, and scalable analog outputs for precise building automation and climate control.
The Rotronic HygroFlex3 HF3 Series is an advanced HVAC transmitter range for high-precision humidity, temperature, and dew point measurement. Powered by AirChip3000 digital technology, HF3 delivers outstanding accuracy, fast response, auto-diagnostics, data logging, and long-term stability—making it an ideal solution for demanding HVAC, cleanroom, and building automation applications.
KEY FEATURES
Core Features
Relative humidity, temperature & dew/frost point measurement
< ±2% RH / ±0.3 K accuracy at 23 °C (standard models)
Hygromer® IN-1 humidity sensor
2,000-point data logging with USB service connector
AirChip3000 auto-correction & diagnostics
Selectable scalable outputs: 0–1 / 0–5 / 0–10 V, 0/4–20 mA
HF32 = 2-wire | HF33 = 3/4-wire
Dew/frost point calculation
Fast response time: t63 < 10 s
Long-term stability: <1% RH/year
FDA CFR21 Part 11 & GAMP compliant
TECHNICAL SPECIFICATIONS
Measurement Performance
| Parameter | Specification |
|---|---|
| RH Range | 0–100% RH |
| Temperature Range | –40…60°C (electronics & sensor) |
| Accuracy | ±2.0% RH / ±0.3 K (±1% RH / ±0.1 K in Type R) |
| Resolution | <0.02% RH / 0.01 K |
| Response Time (t63) | <10 s |
| Long-term Stability | <1% RH/year |
Electrical Characteristics
| Parameter | HF32 (2-Wire) | HF33 (3/4-Wire) |
|---|---|---|
| Supply Voltage | 10–28 VDC | 18–40 VDC / 13–28 VAC |
| Outputs | 0/4–20 mA | 0–1 / 0–5 / 0–10 V + 0/4–20 mA |
| Max Load | ≤500 Ω (mA) | ≥1 kΩ/V (voltage) |
| Power Consumption | max 40 mA | <150 mA |
Mechanical & IP Protection
| Version | Dimensions (mm) | IP Rating | Weight |
|---|---|---|---|
| Wall (W) | 101 × 82 × 43 | IP65 | ~120 g |
| Duct (D) | 232 × 82 × 43 (probe + housing) | IP65 | ~120 g |
| Space (S) | 82 × 82 × 28 | IP65 (Space R without LCD) | ~120 g |
Display (Space Version Only)
Graphic LCD (HF3-S)
HF32S variant = no backlight
User-selectable parameters
Advanced Digital Features
Auto-diagnostics (sensor drift, status)
Automatic correction (AirChip3000)
Alarm functions
Multi-point humidity adjustment
Internal 2000-point data memory
Firmware upgrade via HW4 PC software
USB service connector
APPLICATIONS
HVAC/BMS systems
Ventilation ducts
Cleanrooms & laboratories
Museums & archives
Office spaces (space version)
Pharmaceutical & food environments
Industrial climate monitoring
WHAT’S IN THE BOX
Rotronic HF3 Wall/Duct/Space transmitter
Mounting plate & screws
Polyethylene sensor filter
Quick-start wiring guide
FAQ
Q1. Do all HF3 versions support dew point output?
Yes—dew/frost point is calculated internally using AirChip3000.
Q2. Which HF3 version includes a display?
Only the Space version (S) includes a graphic LCD (HF32S = no backlight).
Q3. What is the main difference between HF32 and HF33?
HF32 = 2-wire (current loop), HF33 = 3/4-wire (voltage or current outputs).
Q4. Is the HF3 suitable for outdoor use?
Wall & duct versions are IP65, suitable for protected outdoor or harsh indoor HVAC environments.
Q5. Can the outputs be scaled?
Yes—both outputs can be scaled to any RH, temperature, or dew point range using HW4.