Skip to main content
Home / Sensors / Formaldehyde Sensor Module CJSH22-CH2O Compact Detector Low Power High Precision VOC

Attributes

Brand -
Category Robotics / STEM Teaching Tools / Sensors
Origin -
Detection Gas Formaldehyde (CH2O)
Model Number CJSH22-CH2O
Operating Voltage 3.3V - 5V DC
Output Signal UART / PWM
Response Time < 30 seconds
Power Consumption < 50mW
Operating Temperature -10°C to 50°C
Dimensions 20mm x 15mm x 8mm
Sensor Life > 5 years
Application Air Quality Monitoring, Smart Home Systems

6 reviews

A

Anonymous

Mar 27, 2026

Rating: 5/5

Low power consumption as advertised

I am using this in a battery-powered device, and the low power draw is a game changer. It detects formaldehyde spikes quickly when I bring new furniture into the room.

A

Anonymous

Mar 22, 2026

Rating: 4/5

Compact and effective

Very tiny form factor which fits perfectly inside my custom enclosure. It reacts well to alcohol-based cleaners too, so keep that in mind during testing.

A

Anonymous

Mar 09, 2026

Rating: 5/5

Perfect for my air quality project

This module is incredibly small and easy to integrate with an ESP32. The readings seem consistent when compared to my standalone meter. Great value for the precision offered.

A

Anonymous

Mar 07, 2026

Rating: 4/5

Good sensitivity, fast shipping

Works well out of the box. It took about 2 minutes to warm up, but then the data stream was stable. Deducting one star because the documentation could be more detailed regarding calibration.

A

Anonymous

Mar 05, 2026

Rating: 5/5

Excellent precision for the price

I was skeptical about the 'high precision' claim at this price point, but it holds up. The voltage requirements are flexible, making it easy to power from various sources.

A

Anonymous

Mar 04, 2026

Rating: 5/5

Reliable industrial grade component

Bought five units for a prototype. All of them performed identically. The UART output is clean and easy to parse. Highly recommended for professional prototypes.

5 FAQ

Q: What is the communication protocol used by the CJSH22-CH2O?

A: The module supports both UART (TTL level) and PWM output. You can select the mode via the configuration pins as described in the datasheet.

Q: How often does the sensor need recalibration?

A: Under normal operating conditions, the sensor maintains calibration for over a year. For critical applications, we suggest an annual check against a reference gas source.

Q: Can this sensor detect other VOCs besides formaldehyde?

A: While optimized specifically for Formaldehyde (CH2O), the sensor may show some cross-sensitivity to other volatile organic compounds like alcohol or benzene, but the primary output is calibrated for CH2O.

Q: Is this suitable for outdoor use in rain?

A: No, this is a bare module and is not water-resistant. It must be housed in a protective enclosure with proper airflow if used in outdoor or humid environments.

Q: Does this module require a warm-up period before giving accurate readings?

A: Yes, we recommend allowing the sensor to warm up for approximately 2 to 3 minutes after powering on to ensure stable and accurate baseline readings.

Explore your interests

View More
All Categories
Best Seller (30)
New List (30)
Heidelberg Printing Press Automatic Blanket Wash Cloth - Non-Woven Cleaning Fabric, 500m Roll

Heidelberg Printing Press Automatic Blanket Wash Cloth - Non-Woven Cleaning Fabric, 500m Roll

$3,185.00

Bucket Pack Natural Wood Colored Pencils Water-Soluble for Kids Coloring and Doodling

Bucket Pack Natural Wood Colored Pencils Water-Soluble for Kids Coloring and Doodling

$6.65

Chunfei Grocery Store Yunm'an GR02 Gravel Bike - Thru-Axle Disc Brake, Lightweight Touring with Multiple Rack Mounts

Chunfei Grocery Store Yunm'an GR02 Gravel Bike - Thru-Axle Disc Brake, Lightweight Touring with Multiple Rack Mounts

$6,444.00

Variable Frequency Drive Power Board ZPOW-591 for ACS880

Variable Frequency Drive Power Board ZPOW-591 for ACS880

$2,200.00

Professional Sketching Eraser Kit - Blending Stumps, Sponges, and Paper Tortillons for Highlight & Shadow Correction

Professional Sketching Eraser Kit - Blending Stumps, Sponges, and Paper Tortillons for Highlight & Shadow Correction

$3.90

Weighted Water Bag with Handle, Thickened PV Mesh Gravity Ballast for Banner Stand Fixation (8KG)

Weighted Water Bag with Handle, Thickened PV Mesh Gravity Ballast for Banner Stand Fixation (8KG)

$35.10

Ultra-Fine Purification Lint-Free Cloth Cleaning Cloth Lens Wipe High Quality 0730 Water-Absorbing Dust Removal UV Nozzle 100 Sheets

Ultra-Fine Purification Lint-Free Cloth Cleaning Cloth Lens Wipe High Quality 0730 Water-Absorbing Dust Removal UV Nozzle 100 Sheets

$96.00

Wen Zhengming Small Regular Script Calligraphy Cards: Li Sao Jing, Thousand Character Classic, Qin Fu, Cao Tang Shi Zhi, Qing Jing Jing, Record of the Drunken Pavilion, Red Cliff Ode

Wen Zhengming Small Regular Script Calligraphy Cards: Li Sao Jing, Thousand Character Classic, Qin Fu, Cao Tang Shi Zhi, Qing Jing Jing, Record of the Drunken Pavilion, Red Cliff Ode

$59.00

Zhizhi Manshu Zhao Mengfu Small Regular Script Collection of Ancient Classics (Vol. 1) - Calligraphy Copybook, Brush Writing Cards, Foldable Practice Cards

Zhizhi Manshu Zhao Mengfu Small Regular Script Collection of Ancient Classics (Vol. 1) - Calligraphy Copybook, Brush Writing Cards, Foldable Practice Cards

$49.00

Language of Drums Motion Path Set - Essential Creativity and Rhythm Teaching Material for Drum Kits and Jazz Drums

Language of Drums Motion Path Set - Essential Creativity and Rhythm Teaching Material for Drum Kits and Jazz Drums

$59.14

onlycook Sink Drain Basket, Faucet-Mounted Food Residue Separator and Washing Strainer - 1 Pack

onlycook Sink Drain Basket, Faucet-Mounted Food Residue Separator and Washing Strainer - 1 Pack

$14.10

Heavy-Duty Wiper Arms and Blades for Trucks and Agricultural Vehicles - Universal Replacement Wiper Rubber Strips

Heavy-Duty Wiper Arms and Blades for Trucks and Agricultural Vehicles - Universal Replacement Wiper Rubber Strips

$5.50

Bus Adapter FEPL-02 for ABB Variable Frequency Drive

Bus Adapter FEPL-02 for ABB Variable Frequency Drive

$1,230.00

Baby National Trend Rattle Toy – Chewable Silicone, Easy-Grip Handle, Soft Sound for Early Learning

Baby National Trend Rattle Toy – Chewable Silicone, Easy-Grip Handle, Soft Sound for Early Learning

$19.90

Palace Museum Creative Stationery: Light & Shadow Graffiti Coloring Book - Exquisite DIY Children's Gift, Ancient Style Watercolor Set for Boys and Girls, Early Learning Art Toy

Palace Museum Creative Stationery: Light & Shadow Graffiti Coloring Book - Exquisite DIY Children's Gift, Ancient Style Watercolor Set for Boys and Girls, Early Learning Art Toy

$29.70

Dongyi Study Room Antique Brass Water Pot, Brush Washer Basin, and Small Spoon Set for Calligraphy (3-Piece)

Dongyi Study Room Antique Brass Water Pot, Brush Washer Basin, and Small Spoon Set for Calligraphy (3-Piece)

$33.10

[Deposit Only] Slightly Round Mid-Heel Shoes – Matte Lambskin Puff Lolita Bow Pumps

[Deposit Only] Slightly Round Mid-Heel Shoes – Matte Lambskin Puff Lolita Bow Pumps

$38.00

Chunfei Grocery Store Yunan GR02 Gravel Bike with Thru-Axle Disc Brakes, Lightweight Touring Setup with Multiple Rack Mounts

Chunfei Grocery Store Yunan GR02 Gravel Bike with Thru-Axle Disc Brakes, Lightweight Touring Setup with Multiple Rack Mounts

$8,934.00

5A Natural Madagascar Rose Quartz Loose Beads, Pink Crystal Rhodonite Single Beads for DIY Jewelry Making Accessories

5A Natural Madagascar Rose Quartz Loose Beads, Pink Crystal Rhodonite Single Beads for DIY Jewelry Making Accessories

$0.70

Mini Portable Sketchbook - Blank Pocket Notebook for Doodling, Sketching, Watercolor, Acrylic, and Marker Art - Square Hand-Drawn Journal

Mini Portable Sketchbook - Blank Pocket Notebook for Doodling, Sketching, Watercolor, Acrylic, and Marker Art - Square Hand-Drawn Journal

$5.53

Kitchen Sink Drain Mat with Raised Slope - Splash-Proof Countertop Organizer for Faucet Areas

Kitchen Sink Drain Mat with Raised Slope - Splash-Proof Countertop Organizer for Faucet Areas

$9.00

Front Wheel Bearing for Hyundai Mistra - Mingtuo Brand - Also Fits Hyundai Sonata and Kia Opirus - Front and Rear Auto Bearings

Front Wheel Bearing for Hyundai Mistra - Mingtuo Brand - Also Fits Hyundai Sonata and Kia Opirus - Front and Rear Auto Bearings

$275.00

White Crystal Loose Beads Donghai Agate Gemstone Gold Rutilated Quartz Obsidian Bracelet Strand Aquamarine Amethyst Single Bead

White Crystal Loose Beads Donghai Agate Gemstone Gold Rutilated Quartz Obsidian Bracelet Strand Aquamarine Amethyst Single Bead

$8.42

Kids Art DIY Stamp Kit - Round Sponge Daubers, Mushroom Head Stamps, and Paint for Graffiti

Kids Art DIY Stamp Kit - Round Sponge Daubers, Mushroom Head Stamps, and Paint for Graffiti

$2.44

YP8 YP-80000 Book Block Pressing Machine Supply Robust Structure Reliable Application

YP8 YP-80000 Book Block Pressing Machine Supply Robust Structure Reliable Application

$23,790.00

Feileniao Four Seasons Flowers Line Drawing Atlas - Chinese Ink Painting Guide for Brush Beginners

Feileniao Four Seasons Flowers Line Drawing Atlas - Chinese Ink Painting Guide for Brush Beginners

$39.90

365 Days! Drummer Training Plan - Beginner Self-Study Guide for Drum Kits and Jazz Drums with Tutorial Audio

365 Days! Drummer Training Plan - Beginner Self-Study Guide for Drum Kits and Jazz Drums with Tutorial Audio

$55.00

New Rechargeable Electric Incense Making Machine – Compact Home Device for Extruding Coil, Sandalwood, and Stick Incense, Manual Incense Crafting Equipment

New Rechargeable Electric Incense Making Machine – Compact Home Device for Extruding Coil, Sandalwood, and Stick Incense, Manual Incense Crafting Equipment

$268.00

Tire Stone Removal Hook, Multi-Function Tool with Built-in Screwdriver for Window Breaking and Self-Defense

Tire Stone Removal Hook, Multi-Function Tool with Built-in Screwdriver for Window Breaking and Self-Defense

$7.51

Pearl Sand Wax, Ice Flower Wax, Floating Aromatherapy Candle Colored Suspended Particles for Atmosphere Decor and DIY Crafts

Pearl Sand Wax, Ice Flower Wax, Floating Aromatherapy Candle Colored Suspended Particles for Atmosphere Decor and DIY Crafts

$5.78