The QAE21 passive immersion temperature sensors are used to measure temperatures in pipes and tanks. They are used mainly for controlling or limiting flow temperature, limiting return temperature and controlling domestic hot water temperature.
This manual describes the Symaro™ insert‑type temperature sensor series QAE21, intended for water‑pipe and tank temperature measurement in HVAC applications. It lists the available model variants, their protective sleeves, immersion lengths, rated pressures and sensor elements (Pt100, LG‑Ni 1000, T1).
The document includes technical parameters such as measurement range, accuracy and time constants, as well as detailed mechanical design, installation notes, engineering considerations, and a complete internal wiring diagram for all sensor types. This manual is written in Chinese.
| Test range | -30 °C to +130 °C |
|---|---|
| Pt100 accuracy | Class B |
| LG‑Ni 1000 accuracy | Specified in chart |
| T1 (PTC) accuracy | Specified in chart |
| Time constant with protective sleeve | ≈ 30 s |
The insertion length must be at least 60 mm.
A stainless‑steel (V4A) protective sleeve must be installed.