Fireye MicroM Flame Safeguard (MC-5000)
Fireye MicroM Flame Safeguard (MC-5000) code 39: Lockout Main Valve
Voltage was detected on the main fuel valve during pilot ignition, locking out the burner.
Safety first. This code involves a gas, flame or electrical hazard. Do not keep resetting it. Leave burner, gas train and high voltage work to a qualified technician. WERCS answers 24/7 at (877) 489-3727.
- Code
- 39
- Name
- Lockout Main Valve
- Controller
- Fireye MicroM Flame Safeguard (MC-5000)
- Type
- Gas valve proving
- What it does
- Lockout: the control shuts down and stays off until it is reset
- Risk
- RED Specialist territory
- Reset
- Needs a manual reset
- Source
- The manufacturer's manual (subscribers see which manual and page)
Updated November 4, 2026
How to fix it
Subscribers get:
- What to do next, in plain words
- What the manual says to do, and the page it is on
- The 1 common cause listed for this code
- The step by step check for this problem, one check at a time
- Booking a live video call with Ben, a master booth technician ($250/hr, paid per call)
Questions about this code
What does Fireye MicroM Flame Safeguard (MC-5000) code 39 mean?
Voltage was detected on the main fuel valve during pilot ignition, locking out the burner.
Is Fireye MicroM Flame Safeguard (MC-5000) code 39 dangerous?
It is graded red, specialist territory: it involves a burner, gas, flame or safety lockout, so leave the repair to a qualified technician.
How do I fix Fireye MicroM Flame Safeguard (MC-5000) code 39?
The manual's fix and the step by step check for this code are in WERCS Diagnose, plans from $49 a month. For help right now, WERCS answers 24/7 at (877) 489-3727.
Other Fireye MicroM Flame Safeguard (MC-5000) codes
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