Riello RS/E BLU Burner Control (REC 27.100A2 with RDI21 display)
Riello RS/E BLU Burner Control (REC 27.100A2 with RDI21 display) code c: 3: c: 3 (alternating with d: 0/1/4/20/68/84)
The system detected an air pressure error at startup, which locks out the burner.
Safety first. This code involves a burner or safety lockout. 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
- c: 3
- Name
- c: 3 (alternating with d: 0/1/4/20/68/84)
- Controller
- Riello RS/E BLU Burner Control (REC 27.100A2 with RDI21 display)
- Type
- Air pressure
- 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
Subscribers get:
- What to do next, in plain words
- Which manufacturer manual it comes from, linked
- The 4 common causes 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 Riello RS/E BLU Burner Control (REC 27.100A2 with RDI21 display) code c: 3 mean?
The system detected an air pressure error at startup, which locks out the burner.
Is Riello RS/E BLU Burner Control (REC 27.100A2 with RDI21 display) code c: 3 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 RS/E BLU Burner Control (REC 27.100A2 with RDI21 display) code c: 3?
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 RS/E BLU Burner Control (REC 27.100A2 with RDI21 display) codes
7 · Extraneous light12 · Loss of flame during operation20 · Air pressure errorc: 2 · c: 2 (alternating with d: 1 / d: 2 / d: c: 4 · c: 4 (alternating with d: 0/1/2 and combc: 7 · c: 7 (alternating with d: 0/3)c: 12 · c: 12 (alternating with d: 0/1/2/3/4/5)c: 14 · c: 14 (alternating with d: 0/1/64)c: 20 · c: 20 (alternating with d: 0/1)c: 21 · c: 21 (alternating with d: 0/1/64)
All 24 Riello RS/E BLU Burner Control (REC 27.100A2 with RDI21 display) codes · Every fault code