Zooz 800 Series Z-Wave Long Range DC Signal Sensor ZEN55 - Alarm Input

In this review the Zooz 800 Series ZEN55 is evaluated as a focused automation add-on for homeowners and installers who want Z-Wave monitoring of hard-wired smoke and CO detectors. The bottom line: this small DC signal sensor is not a replacement life-safety device but a practical way to get dedicated notifications and optional relay control from analog interconnected alarms when paired with a compatible Z-Wave hub. It suits anyone who needs reliable notifications and simple automation tied to physical smoke or CO alarms, provided local codes allow such use.

Key Features

• Dedicated alarm input: Wires to hard-wired interconnected smoke and CO detectors so the hub receives distinct alerts when an alarm is triggered.
• Optional relay control: Built-in 120 V relay lets users add automation for a light or siren as an extra signal when the alarm input fires.
• Long Range ready: Supports Z-Wave Long Range for extended coverage and fewer network dropouts when the hub and software support it.
• Mesh repeater: Acts as a regular Z-Wave repeater to stabilize and extend traditional mesh networks.
• Quick inclusion: Includes SmartStart for simpler and secure network inclusion with supported hubs and controllers.

Who It's For

The ZEN55 is best for homeowners, electricians, and hobbyists who already use a compatible Z-Wave hub such as Hubitat with a custom driver, Home Assistant via Z-Wave JS, Ezlo, or Z-Box. It is ideal when the goal is to add notifications and simple automations tied to existing hard-wired analog smoke or CO detectors without changing the detectors themselves.

This device is not for anyone seeking a primary life-safety device or for use with battery-only alarms. Also, because it is an advanced Z-Wave component, users without a compatible, updated Z-Wave controller or those who prefer basic plug-and-play smart sensors may want to look elsewhere.

Pros & Cons

Pros

• Reliable relay operation reported by customers, with steady pairing and no unexpected disconnects.
• Compact form factor and included pigtail wiring make installation behind switches or in tight enclosures straightforward.
• Pairs quickly with Home Assistant and Hubitat and supports extended range when used with Long Range-capable hubs.

Cons

• Not a life-safety device and cannot replace certified alarm components; users must check local regulations before installation.
• Advanced device that requires a compatible, updated Z-Wave hub and in some cases custom drivers for full functionality.

Specifications

Model Number	ZEN55
Z-Wave Frequency	908.42 MHz
Power	120-240 VAC, 50/60 Hz
Max Load	10 A
Z-Wave Range	Up to 300 ft line of sight (Long Range up to ~1 mile)
Dimensions	1.5 in tall, 1.4 in wide, 0.7 in deep
Operating Temperature	32-104 F (0-40 C)

Our Verdict

The Zooz ZEN55 is a sensible, compact option for adding Z-Wave monitoring and basic automation to hard-wired analog smoke and CO detectors when used with a compatible hub. It offers solid relay functionality and reliable pairing reported by customers, making it good value for users who need notifications and simple scene triggers but understand it is not a certified life-safety replacement.

Frequently Asked Questions

Can I use this with battery-operated smoke alarms?
No. The ZEN55 is for hard-wired interconnected analog smoke and CO detectors only and will not work with battery-only units.

Do I need a hub to use this device?
Yes. A compatible, updated Z-Wave hub is required; tested examples include Z-Box, Hubitat with a custom driver, Home Assistant via Z-Wave JS, and Ezlo.

Is this a replacement for my smoke detector?
No. This is not part of a life-safety system and should only be used as a home automation add-on; check local regulations before installing.