Extech RHT20 Humidity & Temperature Datalogger

  • Datalogs 16,000 readings for both temperature and humidity.
  • User selectable sampling rate from 1 second up to 24 hours.
  • Ideal for monitoring parameters in warehouses, storage rooms, freezers and offices.
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rrp £111.26

now £94.00 (Ex. VAT) £112.80 (Inc. VAT)

rrp £111.26


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"Monitor and Log Temperature & Humidity data"

  • Description

    Extech RHT20 Humidity & Temperature Datalogger

    With the Extech RHT20 Humidity & Temperature datalogger can monitor and log data over long periods of time and then easily transfer the data to a pc for viewing and evaluation. The LCD display provides current or Max/Min temperature, humidity and time information. This meter is shipped fully tested and calibrated and, with proper use, will provide years of reliable service. The RHT20 display and front panel buttons provide a means to view the status of the datalogger, observe the current Temperature or Relative Humidity and to view the MAX and MIN values recorded during a recording session.

    Extech RHT20 Humidity & Temperature datalogger Features:

    • USB interface for easy setup and data download
    • Selectable data sampling rate: 1 second to 24 hours
    • 16,000 Humidity and 16,000 Temperature readings
    • User-programmable alarm thresholds for RH and Temperature
    • LCD displays current readings, Min/Max, and alarm status
    • Complete with 3.6V Lithium battery, mounting bracket with combination lock
    • Includes Windows® 2000, XP, and Vista compatible analysis software
  • Specification

    • Display Multi-function LCD
    • Measurement ranges 0 to 100% RH -40 to 158°F , -40 to 70°C (Resolution 0.1°, 0.1RH)
    • Maximum data points 16,350 Temperature and 16,350 Humidity values
    • Sample rate 1s to 24h selectable
    • Analysis software 2000/XP/ Vista
    • Open input indication "LO" appears on the LCD
    • Low battery indication Empty battery symbol appears on the LCD
    • Power supply 3.6V Lithium Battery
    • Battery life 3 months (approximately)
    • Operating Temperature -40 to 158°F, -40 to 70°C
    • Operating Humidity 0 to 100% RH
    • LCD Operating Temperature -13°F to 158°F (-25°C to 70°C)
    • Dimensions: 94.4 x 48.9 x 31.2mm
    • Weight 3.2oz (90.7g)
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  • Reviews

    Review by Katie Porter (Posted on 24/05/2012)
    We bought this tester after complaints from our clients. We needed to check that deliveries of ice-cream were kept at temperatures guaranteed by our carriers. Guess what! It wasn't, we sent the report to the carrier and the issue has now been resolved. I'm very happy with the product and would highly recommend it to anyone for critical temperature analysis.

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  • Delivery Information

    At we understand the importance of a reliable delivery service when shopping online. Especially when the goods are often essential to your working day. If your goods are required by a certain date please feel free to contact us for an honest and realistic indication whether this can be met. We aim to process all orders we receive within 1 to 3 working days, however from time to time we do have an increased demand for certain products or there might be delays from the manufacturer. In such cases delivery of your equipment may be subject to a minor delay.

    We use DPD/Interlink for all larger items and Royal Mail for smaller items and accessories. With DPD/Interlink you will receive a 1 hour delivery window on the day of delivery via e-mail/text and a notification 15 minutes before arrival so you will not have to wait around all day. You can even manage your booking online and re-arrange delivery for another date or arrange the goods to be left with a neighbour of your choice.

    We also offer delivery options for goods required urgently on certain products, all which are sent by DPD/Interlink.

    Our charges for UK deliveries:

    • FREE Delivery (on select products only): typically 3-5 working days*
    • Standard Delivery at £4.95: 2-3 working days
    • Next Working Day Delivery (on select products only) at £7.50
    • Pre-Noon Next Working Day Delivery (on select products only) at £9.50*
    • Pre-10.30am Next Working Day Delivery (on select products only) at £18.50*
    • Saturday Pre-Noon Delivery (on select products only) at £14.50*
    • Sunday Pre-Noon Delivery (on select products only) at £14.50*

    *UK mainland only

    NOTE! For next working day or Saturday/Sunday delivery options the order MUST be placed no later than 3pm on the working day before delivery is required. After 3pm, please arrange with our staff before selecting a priority delivery service. Priority services are available to UK mainland residents only (this might exclude certain areas in the north of Scotland).

    Customers outside the UK: exports to many countries all over the world. Prices for shipping vary on location and weight/dimensions. Costs are calculated for certain countries at the checkout. If your country is not included in this list please e-mail with your name, address and the items you would like to order for an accurate shipping quote or go to for more information.

    For more information on delivery, please see our terms and conditions.