Air temperature sensors in climate technology: types, purpose, right choice

The task of any HVAC system is to maintain various parameters of the atmosphere in the room at a given level. Temperature is the most important one. And for the safety, for example, of certain products, exhibits or equipment (although humidity or other characteristics may be of no less importance there), and certainly for living people, for whom the main thing is whether they are warm enough and not too hot. It is not for nothing that there are many times more thermometers sold in the world than hygrometers and other similar measuring instruments combined (and the desire to more often control a certain parameter is an indicator of its importance). Therefore, if one or another climatic apparatus is at least somehow automated, has at least one sensor, then it will be an air temperature sensor.

The mentioned importance of temperature is due to its influence on almost all objects and processes in nature - physical, chemical, biological. Accordingly, it can be measured (with greater or lesser convenience, acceptable limits, accuracy, speed) through a variety of manifestations. Hundreds of ways have been invented over thousands of years of history. Here are just a few that are convenient not only for indication, but also for controlling various automation:

• Liquid thermometer (including contact) - a glass capillary with mercury, tinted alcohol, etc. Readings can be taken optically, capacitively or inductively, as well as through a conductor introduced to the required level, with which the liquid comes into contact when the specified temperature is reached. Advantages - the highest accuracy and stability of parameters, it is almost eternal until it is broken, the indication is carried out without electronics. Disadvantages - fragility, bulkiness and inertia, limited range of boiling points and crystallization (or excessive thickening) of the liquid used.

• Bimetallic - converts the thermal deformation of a plate (spring) from two metals with a different coefficient of thermal expansion into rotational or translational movement of the arrow (contact). The accuracy, stability and durability are smaller, the temperature range and mechanical strength are larger. There is an option for a relay (reusable thermal fuse) with two stable states and very fast switching for direct (without electronics) switching of significant currents, but with the inevitable, like any trigger, hysteresis.

In units for space heating / cooling, the temperature sensor can be located both directly near the heat exchanger, and in the outside air at a distance from it - on the wall, in the control panel and other places. In the first case, it responds more reliably and faster to emergency modes, for example, instantly turning off the heater when the fan stops, which prevents more serious accidents or at least idle power consumption. And with a remote location, the sensor more accurately registers and allows you to maintain exactly the average temperature in the room, which depends not only on the temperature at the outlet of the fan coil unit. Some ventilation systems also display or automatically take into account the outdoor temperature in the air intake to select the optimal mode.

Since today electronic thermometers are more often used, where the sensor is integrated into a rather complex circuit, only a highly qualified specialist can decide to replace it with another model.

The Fancoil Motors online store provides an opportunity to buy any components for climate control equipment, for example, an outdoor temperature sensor, the price of which, thanks to our bulk purchases and discounts from old trusted suppliers, may not exceed the cost from the manufacturer.

If you do not immediately see the model you are looking for in the catalog, do not waste time delving into the technical details. One call - and our employees will consult free of charge on the supply of goods that are not in stock or their exact replacement.