IDD Detector

  • Different Product types of Forney's IDD Detector
  • Blue Forney IDD Ultra product
  • Black Forney IDD IIL product
  • Yellow Forney IDD II product
  • White Forney IDD IIU product
  • Forney IDD Detectors Dimension

Product Overview

Forney’s Intelligent Dynamic Detector (IDD) II Series is designed to accurately detect and discriminate the luminous flames produced by burning oil, coal, and lignite fuels.

The IDD-II (Filtered) flame detector is typically used for sensing heavy fuel oil and coal flames. The IDD-IIU (Unfiltered) flame detector is typically used for sensing light fuel oil flames. The IDD-IIL (Lignite) flame detector is specifically designed to sense low flame frequency produced by lignite and high ash coal flames.

The IDD-II Series is used in conjunction with Forney’s supporting amplifier the IDD-9000.  (The DR-6101E, RM-IDD and IDD-IIIA are now obsolete – replaced with the IDD9000 Amplifiers).

The IDD-II’s solid state circuitry amplifies a continuously changing voltage signal transmitted from the lead sulfide sensor when flame is sensed. The signal is then sent to the amplifier by way of a four conductor cable. The amplifier processes the signal and provides outputs to the burner management system.

For trouble-free operation, the detector electronics are potted within the cast steel housing. In addition, the amplifier also initiates a periodic, electronic selfcheck of the sensor and printed circuit board to verify proper operation of the detector assembly.

Products and Accessories

IDD-II Infrared Detector Filtered (#6 Oil & Coal ) Part #38321-21
IDD-IIU Infrared Detector Unfiltered (#2 Oil, #6 Oil & Coal) Part #38321-22
IDD-IIL, Infrared Detector Lignite Fuel Part #38321-23
Cooling Chamber (optional) Part #381071-01


Mounting: 1” NPT sight pipe fitting
Materials: Cast Steel Housing, Potted Electronics
Electrical: Supplied by Amplifier, 50 VDC and 12 VDC
Electrical Connections: MS Bayonet connector supplied with cable, 1/2” flexible conduit required
Cooling Air Requirements: Front mount applications – minimum cooling air flow of 10 scfm (17 m3/hr) at a
maximum temperature of 120°F (48°C)
Fiber optic applications – minimum cooling air flow of 15 scfm (25 m3/hr) at a
maximum temperature of 120°F (48°C)
Temperature Ratings: 32°F to 140°F (0°C to 60°C)
With Cooling Chamber: For ambient temperatures of 140°F to 200°F (60°C to 93°C) the Forney Cooling
Chamber must be used.
Humidity: 0-95% relative humidity, non-condensing
Shipping Weight: 21 oz
Approvals: Factory Mutual (FM)
Sensor / Wavelength: IDD-IIU 400 – 3300nm
IDD-II 700 – 3300nm
IDD-IIL 700 – 3300nm
(The IDD-IIL detector has better flame flicker frequency response at lower flicker
frequency ranges of >5 to 18 Hz)

Detector Heads

IDD-II Spec Sheet
Publication #404005-05

UV-4 Detector Spec Sheet
Publication #404005-17


IDD 9000 Amplifier Spec Sheet
Publication #404005-21

RM-IDD & PM-IDD IIIA Amplifier Spec Sheet (Obsolete)
Publication #404005-16

DR6101E Amplifier Spec Sheet (Obsolete)
Publication #404005-07

Cooling Chambers

IDD Cooling Chamber Spec Sheet
Publication #404005-18

UV-4 Cooling Chamber Spec Sheet
Publication #404005-20

IDD Detector

Features & Benefits

  • Lead Sulfide Sensor
    Sensitive to infrared and visible light radiation prevalent in fuel oil, coal and lignite flames.
  • Dynamic Flame Sensing Circuitry
    Senses only a dynamic flame signal, discriminates flame from hot refractory and other background conditions.
  • Compact, Durable Assembly
    The printed circuit board and sensor are potted within a cast steel housing providing a maintenance free product.
  • Simplified System maintenance
    Quick disconnect, electrical and mechanical connections are used for easy replacement.
  • Fiber Optics
    Optional fixtures are available for fiber optic applications.
  • Factory Mutual Approval
    Factory Mutual (FM) approval means safe operation and lower insurance rates.