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Ultra-High Accuracy and Resolution Digital Thermistor Thermometer


Item# HH42A

Volume discounts available
Volume Discount Schedule
Quantity Price each
1-4 C$1,288.29
5-9 C$1,223.88
10-24 C$1,198.11
25-49 C$1,146.58
50-99 C$1,120.81
100+ C$1,095.05

In stock

Lead Time (If not in stock): 18 weeks
Ultra-High Accuracy and Resolution Digital Thermistor Thermometer HH42A HH42A
  • Works with Standard OMEGA™ “400” Series Thermistor Probes with Phone Jack Termination
  • Ultra-High Accuracy, up to ±0.015°C (±0.027°F)
  • Includes NIST Traceable Calibration Certificate
  • High Resolution, up to 0.01°F or °C

HH42A Model Options

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Edit these specs to order a different model. Not all combinations are valid. Options compatible with previous selections will be in bold.

*Highlighted options are not compatible. Please select a different combination.

Input Type
Minimum Temperature Measurement
Maximum Temperature Measurement
Input Connection Type
Display Type
Accuracy Value
Supply Power
Number of Channels
Communications Protocol

The OMEGA™ HH42A digital thermometer is the most recent addition to a series of instruments based upon our high precision temperature measurement system technology.

This instrument provides the accuracy and resolution needed to meet the measurement needs of a precision laboratory or critical process control and testing functions. Free software is included enabling users to start recording, charting, and storing data in a familiar file format on their PC within minutes of opening the box. A well-defined command set and output data format allows users to easily connect computer systems to the thermometer to create custom displays and report formats. There are a wide range of custom designed application specific thermistor probes that can be selected for use with this instrument. The selected probe would be hardwired to the instrument and calibrated together to meet specific high accuracy requirements. Interchangeable probes with plug-in connectors are also offered.

Resolution: 0.01°C
Temperature Range: -20 to 130°C (-4 to 266°F) (dependent upon probe selection)
Display: °C or °F
Thermometer Measurement Accuracy: ±0.02°C
Total Accuracy and Temperature Range: Combination of the meter and the probe being used
Data Sample Rate: Approximately 7 samples/second
Storage Conditions: 10 to 60°C (50 to 140°F), 0 to 70% RH
Operating Conditions: 10 to 40°C (50 to 104°F), 0 to 85% RH
Output to Computer: USB
Power: 9V battery (included)
Recalibration: Recommended every 12 months

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Rated 4 out of 5 by from Good Unit Unit works great when it works. I have problems with the 1/4 inch phono jack on the unit recoginizing the temp probe. It is intermittent and I have to wiggle or re-insert it a couple of times so I can get it to work.
Date published: 2017-07-10
Rated 5 out of 5 by from Omega Thermometer Great thermometer. We use this handheld thermometer with probe in water baths.
Date published: 2023-10-23
Rated 5 out of 5 by from Excellent temperature meter We have had these units for several years. What is great about them is that I can switch meters and/or probes and the replacements will always read the same to +/- 0.1 C. They really are this good, which means we don't need to do extensive internal calibrations.
Date published: 2020-06-11
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Is there a calibration procedure available for the HH42A Thermometer?

Asked by: NedC
The HH42A meter must be returned for calibration as it is an electronic proprietary process.
Answered by: ApplicationsEngineerANB
Date published: 2021-12-22

Is this product RoHS compliant

Asked by: JBroo
Yes the HH42A is ROHS compliant.
Answered by: ApplicationsEngineerANB
Date published: 2022-11-18

Are there drivers or documentation to communicate with the HH42A with an end user developed application (C, LabVIEW)?

Asked by: BMagiske
Omega provides the Software to communicate and Data log with the HH42A and no additional protocols are available. The drivers are accessible from the Software link of the product page.
Answered by: ANB ENG
Date published: 2021-01-08

Hi, the software in link does not has logging capability, is there another software for that?

Asked by: Anonymous
This is the only Software for the HH42A and has well defined command sets and output data formats. You can copy data into EXCEL for making graphs and data files.
Answered by: Applications Engineer ANB
Date published: 2022-10-28

i am looking to buy Ultra-High Accuracy and Resolution Digital Thermistor Thermometer. Item# HH42A does this model come with probe ?

Asked by: Dipak
Thank you for your inquiry! The model does not come with a probe included.
Answered by: Application Engineer CK
Date published: 2023-01-19

What is the accuracy of this by itself? The datasheet says that there is an accuracy up to +/-0.015 °C and +/-0.02°C. I imagine the accuracy is really in Ω.

Asked by: BenjaminSLC
The HH42A accuracy is +/-0.02C worst case over it's measurement range for the meter only and the probe accuracy would need to be added. For further questions contact the Temperature Engineering group at
Answered by: ApplicationsEngineerANB
Date published: 2023-11-15

Will this Thermometer work with the HSTH-44033-40-PP and the HSTH-44033-120-PP?

Asked by: joep
Yes, the 44033 thermistor element (2252 ohm) is compatible with the HH42A meter which accepts the 2252 ohm thermistors.
Answered by: Temperature
Date published: 2019-12-14

The thermistor probe is already included in the total price of this unit?

Asked by: ORSS
Thank you for your inquiry. No Probe Included.
Answered by: Engineer CB
Date published: 2020-07-08
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