Conventional Heat Detector

FW2522 - Fixed Temperature & Rate-of-Rise Detection

Reliable Heat Sensing • Industrial Applications • Harsh Environment Rated

HEAT DETECTION
2/4 Wire Conventional

Conventional Heat Detector

FW2522

Rated: 135°F / 57°C
2/4 Wire Configurable
Rate-of-Rise
Industrial Grade
Easy Maintenance

The FW2522 Conventional Heat Detector provides reliable fire detection through temperature sensing in environments where smoke detectors are not suitable. Features both fixed temperature and rate-of-rise detection for comprehensive fire protection in industrial, commercial, and harsh environments.

Technical Specifications

Model NumberFW2522
Product NameConventional Heat Detector
Detection TypeFixed Temperature & Rate-of-Rise
System TypeConventional (Non-Addressable)
Wiring Configuration2-Wire or 4-Wire Selectable
Fixed Temperature Rating135°F / 57°C (Standard)
Rate-of-Rise Sensitivity15°F (8.3°C) per minute
CertificationUL 521, EN 54-5
ManufacturerMaple Armor / Tongfang
Warranty3-Year Standard
Operating Voltage12-30VDC
Standby Current20μA @ 24VDC
Alarm Current40mA @ 24VDC
Alarm IndicationRed LED (360° visible)
Test MethodFunctional Test via Test Switch
Operating Temperature Range-20°C to +70°C (-4°F to 158°F)
Storage Temperature-30°C to +80°C (-22°F to 176°F)
Relative Humidity0% to 95% RH (Non-condensing)
Dimensions4.0" diameter x 1.7" height (102mm x 43mm)
Weight5.5 oz (156g)
ColorWhite (Standard), Custom colors available
IP RatingIP44 (Splash resistant)

Product Overview

The FW2522 Conventional Heat Detector is a dual-element heat detector designed for reliable fire detection in environments where smoke detectors are impractical or would cause nuisance alarms. It combines both fixed temperature and rate-of-rise detection technologies for comprehensive fire protection.

Dual Detection Technology

Combines fixed temperature and rate-of-rise detection for maximum reliability.

Flexible Wiring

Configurable for both 2-wire and 4-wire conventional fire alarm systems.

Industrial Grade

Designed for harsh environments where smoke detectors are not suitable.

Detection Technologies
Fixed Temperature

Activates when ambient temperature reaches 135°F (57°C). Factory calibrated for accuracy.

Rate-of-Rise

Detects rapid temperature increases of 15°F (8.3°C) per minute or more.

Intelligent Processing

Microprocessor-based analysis for reliable detection and reduced false alarms.

Temperature Ratings Available

135°F / 57°C (Standard)

Most common rating for general applications

190°F / 88°C (High Temp)

For areas with high ambient temperatures

250°F / 121°C (Extra High)

For industrial ovens, furnaces, etc.

Product Features

Detection Features
  • Dual-element detection (fixed temp & rate-of-rise)
  • Factory calibrated thermal sensors
  • Automatic compensation for ambient temperature
  • Dust and moisture resistant design
  • High immunity to electrical interference
Operational Features
  • 2-wire or 4-wire selectable configuration
  • Built-in test switch for functional testing
  • 360° visible alarm LED indicator
  • Remote indicator output (4-wire configuration)
  • Ultra-low power consumption
Physical Features
  • Compact, low-profile design
  • Twist-lock mounting base
  • Screw terminal connections
  • Tamper-resistant construction
  • High-temperature plastic housing
Safety Features
  • Short-circuit protection
  • Reverse polarity protection
  • Surge and transient protection
  • Automatic reset after alarm
  • Fault monitoring capability
Heat Detector Advantage: Heat detectors are ideal for environments where smoke detectors would cause nuisance alarms or where smoke detection is impractical, such as kitchens, garages, mechanical rooms, and industrial facilities with dust, fumes, or high humidity.

Installation & Configuration

Ceiling Mount
Standard ceiling installation
Wall Mount
Optional wall mounting
Industrial Mount
High bay and industrial
Installation Guidelines
  • Follow NFPA 72 spacing requirements (50' spacing typical)
  • Install in areas of expected heat accumulation
  • Avoid direct exposure to HVAC vents or drafts
  • Maintain minimum 4" clearance from walls and obstructions
  • Consider thermal lag in high ceiling applications
Wiring Configuration
2-Wire Configuration

Power and alarm signals on same pair. Maximum detectors per circuit: 20.

4-Wire Configuration

Separate power and alarm circuits. Allows remote annunciation.

Configuration Jumper

Internal jumper selects between 2-wire and 4-wire operation.

Installation Steps
  1. Select appropriate location based on NFPA 72 requirements
  2. Mount the heat detector base to ceiling or wall
  3. Connect wiring to terminal block (select 2-wire or 4-wire)
  4. Set configuration jumper if using 4-wire mode
  5. Install heat detector head onto base (twist-lock)
  6. Test detector using built-in test switch
  7. Verify alarm LED operation and system integration
Spacing Requirements
Ceiling Height Maximum Spacing Maximum Area per Detector
Up to 10' (3m) 50' (15m) 2500 ft² (232 m²)
10'-30' (3-9m) 30' (9m) 900 ft² (84 m²)
Over 30' (9m) Consult NFPA 72 Engineering required

Applications & Compatibility

Compatible Systems
  • All conventional fire alarm panels
  • Maple Armor conventional systems
  • 2-wire conventional circuits
  • 4-wire conventional circuits
Ideal Applications
  • Commercial kitchens
  • Garages and parking structures
  • Mechanical and electrical rooms
  • Industrial facilities
  • Warehouses and storage areas
Application Scenarios
Commercial Kitchens

Where smoke from cooking would cause nuisance alarms.

Industrial Facilities

Areas with dust, fumes, or high humidity where smoke detectors fail.

Parking Garages

Vehicle exhaust would trigger smoke detectors prematurely.

Benefits

Reliable: No nuisance alarms from dust or humidity

Robust: Suitable for harsh environments

Flexible: 2-wire or 4-wire configuration

Cost-Effective: Lower maintenance than smoke detectors

Easy Maintenance: Simple testing and cleaning

Scalable: Easy to expand existing systems

Comparison with Smoke Detectors
Feature Heat Detector Smoke Detector
Detection Method Temperature increase Smoke particles
Response Time Slower (heat must build) Faster (early warning)
Nuisance Alarms Very low Possible from dust, steam
Suitable Environments Dusty, humid, kitchens Clean, office, residential
Maintenance Low (no cleaning needed) Regular cleaning required