Gravity Formaldehyde (HCHO) Sensor
Description
- High stability and sensitivity
- Automatic temperature compensation
- Wide input voltage(3.3~6V)
- Support DAC and UART output
- Long life(2 years in air)
- High resolution (0.01ppm)
The Gravity Formaldehyde (HCHO) Sensor is an Arduino & Raspberry Pi compatible module, which is the ideal solution for indoor air quality monitor. This is a HCHO (CH2O) sensor module. It can be used to measure HCHO in air. Through it, you can know the air quality. This sensor module is widely used in many air testing applications, such as indoor air quality, real time quality monitoring stations. Many advantages are available, such as strong anti-jamming capability, high stability, ATC, high sensitivity (up to 0.01ppm) and long life (2 years in air). Integrated with Gravity Interface which is easy to used, wide input voltage, and optional output signal.
This is a formaldehyde (HCHO) sensor module with small size, and Arduino compatibility. Through it, you can measure the concentration of formaldehyde in air and know the Real-Time air quality. It can be widely used in many air testing applications, such as indoor air quality, real time quality monitoring stations. Applied in a DIY formaldehyde detector is also suitable.
- Input Voltage: 3.3~6V
- Target Gas: HCHO
- Interference Gas: Alcohol, CO & etc
- Detection Range: 0~5ppm
- Resolution: 0.01ppm
- Warm Up Time: ≤3 minutes
- Response Time: ≤60 seconds
- Resume Time: ≤60 seconds
- Interface Type: Gravity-3Pin
- Output Signal: Optional DAC(0.4~2V,for 0-5ppm) or UART(9600)
- Operating Temp: 0~50℃
- Operating Hum: 15%RH-90%RH(No Condensation)
- Storage Temp: 0~50℃
- Working Life: 2 years (in air)
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Refund Policy
If you are not satisfied with a product purchased from the Site, you may request a return within 30 days from the delivery date, unless the product is listed under the Return Exceptions below or is subject to specific return conditions noted on the product page.
This return policy also applies, as a minimum standard, to products sold and fulfilled by third-party vendors through the Marketplace.
Please review the Return Conditions, Return Exceptions and the process on How to Request a Return Authorization (RA) before initiating a return request.
Returns under this policy concern non-defective products. In the case of a confirmed manufacturing defect, remedies are handled under the Warranty terms, at the Vendor's discretion. See the Warranty section.
Return Conditions
To qualify for a refund under the 30-day return policy, all of the following conditions must be met:
- A valid Return Authorization (RA) number must be obtained prior to returning the product. Returns without an RA number will be refused.
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- The RA number must be included with the return.
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- On-Demand Items — Standard catalogue products not stocked by RobotShop and ordered specifically to fulfill a customer request.
- Professional & Specialized Equipment — See the Professional & Specialized Equipment Warranty page and Professional & Institutional Buyers (B2B) section in the Terms & Conditions.
How to Request a Return Authorization (RA)
While the same return policy applies, these orders require a separate contact process for returns.
- RobotShop Fulfilled Orders → submit a support ticket from your account under My Support Tickets.
- Marketplace Vendor Orders → submit a ticket from your account under My Marketplace Tickets to contact the vendor directly.
Note: Marketplace vendor products are normally labelled with SKUs starting with RM, and identified on the product page with the mention "Sold and fulfilled by [Vendor Name]".


