Key Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | R7861A1026/U |
| Manufacturer | Honeywell |
| Product Type | UV flame amplifier / dynamic self-check amplifier |
| Series Context | Honeywell 7800 Series combustion control system |
| Flame Failure Response | Approximately 2 or 3 seconds |
| Operating Ambient Temp | Approximately -40°F to 140°F / -40°C to 60°C |
| Compatible Detector | C7061 UV flame detector family |
| Compatible Controller Context | 7800 Series relay modules |
| Mounting Style | Plug-in amplifier module |
| Verification Required | Nameplate, revision, relay module model, detector model, application drawing |
Product Introduction
Burners do not forgive bad flame detection. If the amplifier lies about flame, the safety logic lies with it. The Honeywell R7861A1026/U is a UV flame amplifier used with Honeywell’s 7800 Series combustion control architecture, typically paired with a C7061 UV flame detector to sense ultraviolet radiation from gas, oil, or similar fuel flames.In the field, this is the kind of part you only notice when the burner locks out, the flame signal looks unstable, or the safety relay refuses to run. Its real value is not in the catalog description. It is in the dynamic self-check behavior, the flame-fail response timing, and the ability to work cleanly with the correct 7800 Series relay module. If the revision, detector type, and relay module all line up, it is a straightforward plug-in replacement. If they do not, it becomes a troubleshooting headache.
Quality SOP & Tech Pitfalls
The Lab Report
Before this amplifier goes into service, I would check it like this:
- Visual inspection: Examine the housing, label, PCB edge connector, pins, mounting keying, and plastic for cracks, heat damage, corrosion, or bent pins.
- Part-number verification: Confirm R7861A1026/U is clearly marked and matches the purchase order.
- Revision / date-code check: Record any revision, date code, lot code, serial number, or secondary markings.
- Counterfeit / gray-market screening: Compare label print quality, Honeywell branding, packaging, and supplier traceability.
- Mechanical fit check: Verify the plug-in edge connector matches the 7800 Series relay module base.
- Electrical checks: Use a multimeter such as a Fluke 115 for continuity, supply presence, and obvious short/open checks where safe and applicable.
- Live test on test rack: Only perform functional testing if the correct 7800 Series relay module, C7061 detector, and burner simulation setup are available.
- ESD and contamination control: Handle as an electronic module; keep it clean, dry, and sealed before installation.
The Engineer’s Warning
The worst mistake with R7861A1026/U is treating it like a generic flame amplifier.
- It is not a universal UV amplifier.
- It is meant for use with C7061 UV detectors and 7800 Series relay modules.
- A different Honeywell flame amplifier may look similar but have different self-check logic, response timing, or connector keying.
- If the flame detector is not C7061, or the relay module is not a compatible 7800 Series unit, do not assume this amplifier will work.
I have seen burners lock out repeatedly after someone installed a “close enough” flame amplifier. The flame was there. The detector saw it. The control logic still rejected it because the amplifier, detector family, or relay module pairing was wrong. Take a photo of the old label, the relay module model, and the detector model before ordering.
Installation & Configuration Guide
1. Pre-Installation
⚠️ Lock out all fuel, ignition power, line voltage, and burner control power before removing the old amplifier.
⚠️ Photograph the existing amplifier label, relay module slot position, wiring, and detector connections.
⚠️ Confirm the relay module is a compatible Honeywell 7800 Series unit and the detector is a C7061-type UV detector.Before starting:
- Place the burner system in a safe maintenance state.
- Confirm lockout/tagout and combustion safety procedures.
- Verify the replacement matches R7861A1026/U and the existing application.
- Check whether the system requires a flame test, safety trial run, or combustion qualification after installation.
2. Removal
- Label the amplifier location and orientation if the slot or base is not clearly marked.
- Remove the old amplifier carefully from the relay module base.
- Do not pry on the PCB edge connector.
- Inspect the relay module socket for corrosion, bent pins, burnt contacts, or contamination.
- Store the removed amplifier in an ESD-safe container if it will be evaluated or returned.
3. Installation
- Compare Honeywell R7861A1026/U to the original amplifier side by side.
- Confirm the label, connector orientation, mounting keying, and physical condition match.
- Copy any module position, jumper, or configuration details from the old installation before removing it.
- Seat the amplifier fully and evenly into the correct relay module slot.
- Do not force it. If it does not seat cleanly, check orientation and pin alignment.
- Reconnect detector wiring only as shown in the OEM drawing.
4. Power-On & Testing
- Perform a visual check before restoring power.
- Restore power only after all guards, wiring, and fuel safety checks are complete.
- Watch for normal boot, flame signal indication, and absence of flame-failure alarms during a valid flame call.
- Verify flame failure response if the system procedure requires it.
- Do not return the burner to production until the full safety sequence, flame proving, and OEM startup checks are complete.
- Log the installed part number, relay module model, detector model, and equipment location.
Compatible Replacement Models
| Replacement Option | Compatibility | Notes |
|---|---|---|
| Honeywell R7861A1026/U, same revision | ✅ Drop-in replacement | Best option if label, relay module, and detector pairing all match. |
| Honeywell R7861A1026 without /U suffix | ⚠️ Verify carefully | May be related; confirm revision, application note, and OEM documentation before use. |
| Other R7861A variants | ⚠️ Not automatic | Same family does not guarantee identical flame response, self-check behavior, or relay module compatibility. |
| R7847 / R7849 / R7886 family | ❌ Not direct | Different amplifier families; do not substitute without OEM confirmation. |
| Non-Honeywell UV amplifier | ❌ Not recommended | High risk of safety, fitment, and combustion control issues. |
Before accepting any substitute, confirm:
- Exact Honeywell part number
- Revision or secondary marking
- 7800 Series relay module model
- UV detector model
- Flame failure response time requirement
- Operating temperature and mounting environment
- OEM wiring diagram and combustion safety procedure
Frequently Asked Questions
1. What is Honeywell R7861A1026/U?
It is a Honeywell UV flame amplifier used with 7800 Series combustion control systems. Its job is to work with a C7061 UV flame detector and a 7800 Series relay module to confirm that a valid flame is present during burner operation.2. What does the “/U” mean in R7861A1026/U?
The exact meaning of the /U suffix should be confirmed with the Honeywell datasheet or the product label. In many Honeywell part numbers, suffixes can indicate revision, packaging, agency marking, or manufacturing variation. Do not assume it is interchangeable with R7861A1026 unless documentation says so.3. Can I use R7861A1026/U with any UV detector?
No. It is intended for use with C7061 UV flame detectors and compatible 7800 Series relay modules. If your detector is not C7061, or your relay module is not a compatible 7800 Series unit, this amplifier may not work correctly.4. Can I hot-swap this amplifier while the burner is running?
No. Do not remove or install flame amplifiers on a live burner. Lock out fuel and control power, follow combustion safety procedures, and treat the system as energized until verified de-energized.5. Is R7861A1026/U interchangeable with R7847, R7849, or R7886 amplifiers?
Not automatically. Those are related Honeywell flame amplifier families, but they are not guaranteed drop-in replacements. Mixing families can change flame detection behavior, self-check logic, response timing, and safety operation.6. What should I check before buying R7861A1026/U?
Send the full photo of the old amplifier label, the 7800 Series relay module model, the UV detector model, the equipment model, and the reason for replacement. That information prevents most wrong-part purchases.7. What if the new amplifier installs but the burner still locks out?
Check the obvious first: detector alignment, quartz window cleanliness, detector wiring, relay module socket condition, flame signal test point, and correct amplifier seating. If those are good, verify the flame failure response setting and relay module compatibility. The OEM manual has the final say on safe commissioning.
