Thermometers
Thermometers are pointer instruments that display the temperature of the fluid inside a pipeline or tank on a dial without using energy. The category includes back and bottom connection bimetal thermometers, heating thermometers, contact thermometers and the stainless thermowells used with them.
Measurement is made by the helical bimetal strip inside the stem twisting with temperature and turning the pointer. These EN 13190 thermometers are offered with Ø63, Ø100 and Ø160 mm dials, accuracy class CL 2.0, scales from −30 °C up to 500 °C and immersion lengths of 50–1000 mm.
Main Applications
- Reading boiler outlet water on the dial in heating installations
- Storage temperature in calorifiers, accumulation and buffer tanks
- Temperatures down to −30 °C in chilled water and chiller circuits
- Measurement with 300–500 °C scales on steam and thermal oil lines
- Alarm or control signal at a set temperature with contact types
Technical Data
| Measuring element | Helical bimetal coil |
|---|---|
| Dial sizes | Ø63, Ø100, Ø160 mm |
| Scale ranges | From −30…200 °C to −30…500 °C; 0/60 … 0/500 °C |
| Accuracy class | CL 2.0 |
| Process connection | G1/2″ B; options 1/2″ NPT, G3/4″, 3/4″ NPT, G1″ |
| Connection position | Back (axial) or bottom (radial) |
| Bimetal stem diameter | Ø9 mm |
| Thermowell diameter | Ø12 mm |
| Immersion length | Ø63: 50–500 · Ø100: 50–1000 · Ø160: 100–1000 mm |
| Max. working pressure | 25 bar |
| Degree of protection | IP51 |
| Standard | EN 13190 |
Material Options
| Part | Ø63 dial | Ø100 dial | Ø160 dial |
|---|---|---|---|
| Case and bezel | AISI 430 | AISI 430 | Black painted steel |
| Window | Polycarbonate (≤120 °C) or glass | Glass | Glass |
| Dial | Aluminium | Aluminium | Aluminium |
| Pointer | Plastic (≤160 °C) or aluminium | Plastic (≤160 °C) or aluminium | Aluminium |
| Bimetal cover | Brass | Brass | Brass |
| Thermowell | AISI 316L or brass | AISI 316L or brass (316L for bottom connection) | AISI 316L or brass |
Note: The polycarbonate window is used up to 120 °C and the plastic pointer up to 160 °C; for higher scales the glass window and aluminium pointer version is chosen. Values are from the manufacturer data sheet; contact ratings of contact thermometers vary by model.
Advantages
Unpowered indication
- The bimetal element transfers temperature directly to the pointer.
- No cable or power connection is needed.
Three dial sizes
- Ø63 suits tight spaces, Ø160 reading from a distance.
- Different sizes use the same G1/2″ connection.
Long immersion
- Stem lengths up to 1000 mm can be selected.
- The tip reaches the flow centre in large pipes and tanks.
Thermowell measuring point
- The thermometer works inside a Ø12 mm pocket without fluid contact.
- The pocket can be AISI 316L or brass.
Construction and Design Features
- Helical bimetal measuring element with brass cover
- Aluminium dial and pointer
- AISI 430 or painted steel case, glass or polycarbonate window
- G1/2″ B threaded back or bottom connection
- Ø12 mm AISI 316L or brass thermowell
Send us the scale range, dial size, connection position and immersion length via the Request a Quote form and we will prepare the thermometer and thermowell set together.
How to Choose?
- Consider the reading distanceChoose Ø63 for points read up close and Ø100 or Ø160 for points read from afar.
- Choose the connection positionPrefer back (axial) or bottom (radial) connection depending on the viewing direction.
- Set the scaleChoose a scale such as 0/120, 0/160 or 0/500 °C that covers the highest operating temperature.
- Calculate the immersion lengthThe stem must be long enough to reach the flow zone in the pipe or tank.
- Match the thermowellThermowell length and connection thread must suit the thermometer stem.
Complementary Products
Why ORFA?
Types of Thermometers
Bimetal Thermometers
Bimetal thermometers show temperature on a dial using the different thermal expansion of two metals.
Details →
Gas-Filled Thermometers
Gas-filled thermometers show temperature remotely through the pressure change of gas in a capillary.
Details →
Contact Thermometers
Contact thermometers show temperature and also switch an electrical contact at a set value.
Details →
Industrial Machine Thermometers
Industrial machine thermometers are sturdy, sheathed thermometers used to read temperature on pipelines and machines.
Details →Other Temperature Measurement and Control Equipment
Temperature Controllers
Temperature controllers keep the process at the desired temperature by controlling heaters, coolers or valves based on the sensor value.
Details →
Temperature Sensors – Thermocouples
Temperature sensors and thermocouples measure process temperature and send an electrical signal to a controller or indicator.
Details →
Thermostats
Thermostats change contact when the set temperature is reached, switching a burner, pump or heater on or off.
Details →Get a quote for your project
Our sales team will prepare the best solution for your needs.