• Extech RH390 Precision Psychrometer

Extech RH390 Precision Psychrometer

Extech RH390 Precision Psychrometer

 4.4 | (8 Reviews)
$255.00 USD
$255.00 USD $263.00 USD
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Extech RH390 Precision Psychrometer

Extech RH390 Precision Psychrometer

 4.4 | (8 Reviews)
$255.00
$255.00 $263.00
SAVE 3% Sold out
  • 14-Day Money Back Guarantee

Product Description

The Extech RH390 Precision Psychrometer offers highly accurate humidity and temperature measurement for water restoration professionals. This compact, portable device measures dew point, wet bulb, and relative humidity with ±2% accuracy, helping prevent mold growth. Featuring a dual-illuminated display and 2-year warranty, it’s essential for moisture monitoring.

Our guarantee to you

At Flood Buds, we are committed to providing you with high-quality products and exceptional customer service. We want you to be completely satisfied with your purchase, and we offer a 14-day guarantee to ensure we earn your trust. If you are not satisfied with your purchase for any reason, please contact us at customer@floodbuds.com

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Extech RH390 Precision Psychrometer

Extech RH390 Measure Humidity and Temperature

The Extech RH390 Precision Psychrometer is an essential tool for water restoration professionals who require precise environmental monitoring. Designed to measure humidity, temperature, dew point, and wet bulb temperatures simultaneously, this handheld device ensures accurate readings with ±2% relative humidity accuracy and ±1.8°F temperature accuracy. Its dual-illuminated display allows quick switching between wet bulb, dew point, and temperature readings, making it ideal for assessing moisture levels during water damage restoration.

The RH390 covers a broad temperature range from -22°F to 199°F (-30°C to 100°C) and full-spectrum relative humidity from 0 to 100%, providing comprehensive data to help prevent mold growth and ensure proper drying. Compact and lightweight at just 7 ounces, it’s powered by a single 9V battery and comes with a protective carrying case for on-the-go use. Certified with CE and backed by a 2-year warranty, the Extech RH390 is a reliable, professional-grade moisture detection tool perfect for any water restoration project.

Extech RH390 Precision Psychrometer

RH390 Helps Confirm Dry-Out Status Before Teardown Begins

✅ Accurate Humidity Measurement: ±2% relative humidity accuracy ensures reliable moisture data
✅ Comprehensive Temperature Range: Measures -22°F to 199°F for versatile site conditions
✅ Multiple Readings Display: Simultaneously view dew point, wet bulb, and temperature for thorough analysis

Extech RH390 Precision Psychrometer

RH390 Extech Stops Call-Backs By Proving Job Is Done

✅ Lightweight and Compact: Weighs only 7 ounces, ideal for field use
✅ Long Battery Life: Powered by a single 9V battery for extended operation
✅ Protective Carrying Case: Includes durable case to safeguard device during transport

Extech RH390 Precision Psychrometer

What's Included in the Box?

✅ Precision Psychrometer Meter

✅ Carrying Case

✅ 9V Battery

✅ Comprehensive owner’s manual

✅ 2-year parts warranty for peace of mind

✅ Free $25 Gift Card

RH390 Documents & Downloads

📄 RH390 User Manual

📁 RH390 Product Sheet

Extech RH390 Top Reviews 4.4/5 ⭐⭐⭐⭐

  • Lisa Whitman

    ⭐⭐⭐⭐⭐


    This psychrometer is essential for our restoration business. The dual display is very convenient, and the accuracy has improved our drying process significantly. Highly recommend!

  • Ryan Caldwell

    ⭐⭐⭐⭐

    Compact and precise, the RH390 is perfect for on-site moisture checks. Battery life is solid, and the 2-year warranty gives peace of mind. Great investment for pros!

  • Ryan McAllister

    ⭐⭐⭐⭐

    The Extech RH390 is a reliable tool for my water restoration jobs. Accurate readings and easy to carry. Helps me monitor moisture and prevent mold effectively

Frequently Asked Questions

What are the specifications?

General Specifications:
Dew Point: -22 to 199 °F (-30 to 100 °C)
Relative Humidity: 0 to 100%
Temperature (Air): -22 to 199 °F (-30 to 100 °C)
Wet Bulb: 32 to 176 °F (0 to 80 °C)
Accuracy & Resolution:
Relative Humidity Accuracy: ±2% between 20% and 90% RH
Temperature Accuracy: ±1.8 °F (1 °C)
Resolution: 0.1% RH, 0.1 °F/°C
Physical & Power Details:
Dimensions: 7.8 × 1.7 × 1.3 inches (200 × 45 × 33 mm)
Weight: 7 oz (200 g)
Power: 1 × 9V battery
Warranty: 2 years
Certifications: CE

How long does shipping take?

95% of orders are delivered to our customers within 5 business days

Maximum 10 business days for more remote locations

Overnight shipping is available for emergency equipment needs for an additional charge. Feel free to call us for our options at 833-356-6323.

Can I return or exchange?

Yes we allow returns without issue. If you are not happy with the product for whatever reason and within 14 days of purchase, we will accept the return of the product and refund your purchase

What types of payment do we accept?

We accept major credit cards (Visa, Mastercard, American Express), digital wallets (Apple Pay, Google Pay, Shop Pay) and PayPal

How long does it take to be refunded?

We accept returns for a full refund if you would like to return within 14 days.

Once we receive the product back from you, we will issue the refund within 10 business days or less.

Please review our shipping and return policy for full information.

How will I be notified the product has shipped?

From the moment we ship your product, you will receive an email confirmation with tracking information.

What if my product arrives damaged?

Please contact us as soon as possible. We will coordinate with you to get new equipment sent. Reach out to customer@floodbuds.com

Do you have a restocking fee for returns?

Flood Buds does not charge any restocking fees.

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