Key Technical Specifications
- Product Model: 95DSS2-1 / 95DSS2-1CEX
- Manufacturer: FIREYE (Honeywell/Forney)
- Product Type: Integrated Microprocessor Flame Scanner
- Sensor Type: UV, IR, or Dual (IR/UV) depending on specific suffix
- Supply Voltage: 24 VDC
- Electrical Connection: 12-pin quick disconnect or 10ft cable (CG models)
- Relay Output: Internal SPDT Flame Relay (ON/OFF thresholds adjustable)
- Display: 8-character alphanumeric LED display
- Interface: 4-button keypad for local configuration
- Self-Diagnostic: Electronic self-testing (no mechanical shutter required)
- Mounting: Standard 1-inch NPT thread (requires installation flange)
Product Introduction
Burners don’t care about your maintenance schedule. If the flame goes out and the scanner doesn’t catch it in milliseconds, you’re looking at a furnace explosion. The FIREYE 95DSS2-1 is an InSight series flame scanner that sits right in the line of fire, watching the burner. It uses solid-state sensors to detect the specific flicker frequency of your flame and trips the internal relay the second it loses sight of it. No remote amplifiers, no messy external wiring.I’ve installed hundreds of these on industrial boilers. Engineers love them because they have a built-in LED display and keypad right on the probe. You can stand at the burner and tune the ON/OFF thresholds manually without running back to the control panel. Just remember: this thing runs on 24 VDC. Hook it up to 120V and you’ll have a very expensive paperweight. Also, the CEX variant is your explosion-proof version for classified areas—don’t mix them up.
Quality SOP & Tech Pitfalls
The Lab Report:
Before a 95DSS2-1 leaves our bench, it gets a thorough check. We inspect the sensor window for scratches or coating that could blind it. Then it goes on a 24VDC test bench where we verify the internal relay clicks at the correct threshold. We check the LED display for dead pixels and test all four keypad buttons. Finally, we verify the 8-character display boots up correctly and log the firmware revision before sealing it in anti-static packaging.The Engineer’s Warning:
Here’s the number one way guys kill these scanners: they forget the cooling air. If you’re mounting this on a boiler that runs hot, and you don’t plumb in cooling air to the 3/8″ NPT port, the sensor will bake and fail in weeks. I’ve seen a $3,000 scanner melt because someone thought “it’ll be fine.” It wasn’t. Also, when you wire the 12-pin connector, double-check your pinout. Swapping the relay common and NO contacts means your safety circuit will always think there’s a flame. That’s a catastrophic failure waiting to happen. Always verify with a multimeter before putting the boiler in auto.
Installation & Configuration Guide
- Pre-Installation: ⚠️ Lock out and tag out the burner management system. Verify zero energy. Photograph the old scanner’s wiring at the 12-pin connector. If using a cooling air line, verify it’s plumbed and flowing.
- Removal: Disconnect the 12-pin connector or cut the cable (if hardwired, label every wire). Unscrew the scanner from the mounting flange. Inspect the flange gasket—replace it if it’s cracked or compressed.
- Installation: Thread the new 95DSS2-1 into the flange. Hand-tighten, then give it a quarter-turn with a wrench. Do not overtighten. Connect the 12-pin plug, ensuring it seats fully and locks. Reconnect cooling air if applicable.
- Power-On & Testing: Restore 24 VDC power. The LED display should light up. Use the 4-button keypad to enter the setup menu. Set the modulation rate to match your burner’s flicker frequency. Perform a flame simulation test (or light the burner) and verify the internal relay energizes and the BMS sees the flame signal.
Compatible Replacement Models
| Compatibility | Model / Note | Action Required |
|---|---|---|
| ✅ Drop-in | 95DSS2-1CEX | Direct replacement for hazardous locations. Same specs, explosion-proof housing. |
| ✅ Drop-in | 95DSS3-1 | Newer InSight II generation. Same mounting, improved diagnostics. |
| ⚠️ Verify | 95UVS2-1 | UV-only version. Confirm your flame produces sufficient UV radiation before swapping. |
| ❌ Not Compatible | 85UVF1-1 | Older UV scanner style. Different mounting and wiring. Requires flange and wiring changes. |
Frequently Asked Questions
Do I need a remote flame amplifier with this scanner?
No. The 95DSS2-1 has the amplifier and relay built right into the probe. That’s the whole point of the InSight series. You just run 24VDC and the relay contacts back to the BMS.Can I use this for a gas-only burner?
Yes, but make sure you have the right sensor. For gas flames, UV sensors work great. If you’re burning oil or a mix, you might need the IR or dual-spectrum version. Check your flame’s emission spectrum against the scanner’s sensitivity curve.How do I know if the scanner is seeing the flame properly?
Look at the 8-character LED display. It shows the real-time signal strength. When the flame is lit, you should see a strong, stable reading. If it’s bouncing around near the OFF threshold, your sensor window might be dirty, or the scanner is pointed slightly off-center.Is the CEX version really necessary?
If your burner is in a classified hazardous area (Class I Div 1 or 2), absolutely. The CEX housing is rated for explosive atmospheres. Putting a standard scanner in a hazardous zone is a code violation and a safety risk.What if the display is blank after power-up?
Check your 24 VDC supply at the connector. If power is good and the display is still dead, the internal fuse or power supply circuit may have failed. Don’t keep cycling power. Pull it and send it back for evaluation.How often should I clean the sensor window?
Depends on your environment. In a clean gas boiler, maybe annually. In a dirty oil-fired furnace, check it every 3-6 months. A dirty window is the most common cause of false flame failures. Wipe it with a soft cloth and glass cleaner—never use abrasives.
