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Riello RDB 2.2 Burner Control (MO 535 - MPF)

Riello RDB 2.2 Burner Control (MO 535 - MPF) Red steady on: Reset button: steady red

The burner control locks out because no flame was established at the end of the safety time.

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
Red steady on
Name
Reset button: steady red
Controller
Riello RDB 2.2 Burner Control (MO 535 - MPF)
Type
Ignition lockout
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 July 23, 2026

How to fix it

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  • What to do next, in plain words
  • Which manufacturer manual it comes from, linked
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Questions about this code

What does Riello RDB 2.2 Burner Control (MO 535 - MPF) Red steady on mean?

The burner control locks out because no flame was established at the end of the safety time.

Is Riello RDB 2.2 Burner Control (MO 535 - MPF) Red steady on 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 Riello RDB 2.2 Burner Control (MO 535 - MPF) Red steady on?

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 Riello RDB 2.2 Burner Control (MO 535 - MPF) codes

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