Introduction
The Kidde Wireless Hardwired Smoke Detector, 10-Year Battery Backup, Voice Alerts, Photoelectric Sensor Wire-Free Interconnect Combination Alarm, model p4010ACSCO-W, is designed to provide early warning of smoke, fire, and carbon monoxide (CO) gas. It utilizes photoelectric sensor technology for visible fire particles and an electrochemical sensor for CO gas. This alarm is powered by a 120V wired source with a 10-year sealed lithium battery backup, ensuring continuous protection even during power outages. Its wire-free interconnectivity allows multiple Kidde devices to communicate, ensuring that when one alarm sounds, they all do, enhancing household safety.

Figure 1: Front view of the Kidde p4010ACSCO-W combination alarm, showing the central test/hush button and LED indicator ring.
Key Features
- Dual Sensor Technology: Photoelectric sensor for smoldering fires and electrochemical sensor for carbon monoxide.
- Power Source: 120V wired power with a 10-year sealed lithium battery backup.
- Voice Alerts: Announces "Fire!", "Warning! Carbon Monoxide!", or "Replace Alarm!" for clear communication.
- Wire-Free Interconnection: Extends coverage without additional wiring, allowing up to 24 Kidde devices (18 initiating) to communicate.
- Ambient Light Sensing: Prevents late-night battery chirps in dark conditions.
- LED Indicators: Green for normal operation, amber for error, red for alarm.
- Test/Hush Button: Allows testing and silencing of nuisance alarms.
- UL Listed: Certified for safety standards.
Setup and Installation
The Kidde p4010ACSCO-W alarm is designed for hardwired installation. Ensure power is off at the circuit breaker before beginning installation. Follow all local electrical codes and the detailed instructions provided in the full user guide for proper wiring and mounting.

Figure 2: The Kidde alarm is designed for easy installation on ceilings or walls.
Wire-Free Interconnection Setup
This alarm features wire-free interconnection, allowing multiple units to communicate without additional wiring between them. This significantly enhances early warning by ensuring all interconnected alarms sound when one detects a hazard. The setup process involves powering on the devices and initiating a connection sequence.
Video 1: Quick setup guide for Kidde Interconnected Combo Smoke and Carbon Monoxide Alarm. This video demonstrates how to power up multiple devices, enter setup mode, and connect them wirelessly to form a network, ensuring all alarms sound simultaneously when a threat is detected.
For detailed step-by-step installation and interconnection instructions, please refer to the comprehensive User Guide (PDF) available on the product page or via the QR code on the back of the unit.

Figure 3: The alarm can interconnect with up to 24 Kidde devices, with 18 capable of initiating an alarm.

Figure 4: Recommended placement guide for smoke and carbon monoxide alarms within a home, emphasizing installation on every level and near bedrooms.
Operation
Voice Alerts and Alarm Signals
When smoke or fire is detected, the alarm will sound an 85-decibel alarm, the ring on the detector will turn red, and a clear voice alert will announce, "Fire! Fire!". For carbon monoxide detection, the voice alert will be "Warning! Carbon Monoxide!".
LED Warning Light Indicators
- Green Light: Indicates the unit is in proper working operation.
- Amber Light: Indicates an operating error or fault.
- Red Light: Indicates smoke or fire detection.
Test/Hush Button
The large central button on the alarm serves as both a test and hush button. Pressing it allows you to test the alarm's functionality and battery operations. It can also be used to silence nuisance alarms that may occur from cooking or shower steam.
Maintenance
Battery Backup
The alarm is equipped with a 10-year sealed lithium battery backup, eliminating the need for battery replacements throughout its lifespan and providing continuous coverage during power failures.
End-of-Life Alert
When the smoke alarm reaches the end of its 10-year life span, the detector will announce, "Replace Alarm!" This indicates that the unit needs to be replaced to ensure continued protection.
Ambient Light Sensing
An Ambient Light Sensing feature helps to prevent the alarm from chirping in dark conditions, establishing a day/night cycle to avoid nuisance chirps during nighttime hours.
Troubleshooting
For common issues such as nuisance alarms, chirping, or power-related problems, refer to the comprehensive Troubleshooting Guide (PDF). This guide provides detailed steps to diagnose and resolve various operational concerns.

Figure 5: The back of the alarm provides product details and a QR code for additional information and support. (QR code link: https://goo.gl/9RYBLo)
Specifications
| Attribute | Value |
|---|---|
| Brand | Kidde |
| Model Number | p4010ACSCO-W |
| Style | Hardwired Combination Carbon Monoxide & Smoke Detector |
| Power Source | Hardwired (120 Volts AC) |
| Battery Backup | 10-Year Sealed Lithium Battery (included) |
| Color | White |
| Product Dimensions | 5.59"D x 5.59"W x 1.91"H |
| Item Weight | 9.6 ounces |
| Alarm Type | Audible (85-decibel) with Voice Alerts |
| Operating Humidity | 10% to 95% relative humidity, non-condensing |
| Compatible Devices | Up to 24 Kidde devices (18 initiating) |
| Upper Temperature Rating | 100 Degrees Fahrenheit |
| Sensor Type | Photoelectric (smoke) & Electrochemical (CO) |
| Material | Plastic |
| Installation Method | Mounted |
| Included Components | Combination CO & Smoke Alarm, Quick Start Guide, mounting bracket, mounting hardware, wiring harness |
| UL Certified | Yes |
Warranty and Support
The Kidde p4010ACSCO-W Combination Alarm comes with a 10-year limited manufacturer's warranty on the alarm unit. This warranty begins when the alarm is powered on. If the power-on date is unknown, it should be assumed that replacement is needed after 10 years from the manufacturing date.
For further assistance, detailed user guides, or to contact customer support, please refer to the official Kidde website or the documentation provided with your product. The User Guide (PDF) and Instructions for Use (IFU) (PDF) are available for download.





