HH25U-Series

Supported Applications

The HH-25U is a handheld, single-input thermocouple thermometer that accepts Type K, J, and T thermocouples, making it a versatile tool for spot-checking and troubleshooting temperature across a wide span of tasks. With a large LCD, auto power off, data hold, and switchable °C/°F units, it is designed for fast, high-accuracy readings in the field, on the bench, or on the production floor.

Its high-accuracy 0.1% class performance and broad measuring range suit HVAC service, laboratory and QA measurements, equipment maintenance, and general process spot-checks. Maximum, minimum, and hold functions let a technician capture peak values or freeze a reading, while a low-battery indicator flags when the supplied 9V battery needs replacing.

Thermocouples are sold separately, so the user can match the probe type to the application. As a handling note, always plug the thermocouple sensor in before turning on the meter, and confirm correct polarity, or the LCD readings will be meaningless.

Operating Conditions & Performance

The HH-25U delivers high-accuracy measurement with a resolution of 0.1°C (0.1°F), switching to 1°C/1°F over 1000°C. Accuracy is best in class for the Type K input at ±(0.1% rdg + 0.5°C) across -50 to 1370°C, and ±(0.1% rdg + 2°C) elsewhere. The meter also applies a temperature coefficient of 0.1 times the applicable accuracy specification per °C from 0°C to 18°C and 28°C to 50°C (32°F to 64°F and 82°F to 122°F).

The instrument operates in ambient conditions of -10 to 50°C (14 to 122°F), runs on a single 9V battery, and measures 159 x 55 x 38 mm (6.25 x 2.16 x 1.49"). It is CE marked and RoHS compliant. To preserve battery life, remove the battery when the meter is not in use.

Configuration Options

Although offered as a single model, the HH-25U's capability shifts with the thermocouple type selected, each covering a different measuring range and accuracy:

• Type K: -200 to 1370°C (-328 to 2498°F), accuracy ±(0.1% rdg + 0.5°C) for -50 to 1370°C, others ±(0.1% rdg + 2°C)
• Type J: -80 to 760°C (-112 to 1400°F), accuracy ±1% of rdg + 1°C/2°F
• Type T: -80 to 400°C (-112 to 752°F), accuracy ±1% of rdg + 1% for 200 to 400°C, others ±0.4% rdg + 0.6°C/1.2°F

In every case the reading resolution is 0.1°C (0.1°F), coarsening to 1°C/1°F above 1000°C, and the same maximum, minimum, and hold functions are available regardless of thermocouple type.

Key Product Differences

The series comprises one meter and a matching accessory:

• HH-25U — Single J/K/T input thermocouple thermometer, supplied with a 9V battery and operation manual
• SC-25U — Carrying case (accessory)

Type J, K, or T thermocouples are ordered separately from the Omega thermocouple selection to suit the specific measurement.