Combustion Chamber + Heat Exchanger Vaillant VMW 226/3-3 (Giannoni GM30-45-004-09) Ref. GM30-45-004-09
RefurbishedVaillantCombustion chambersGiannoni

Combustion Chamber + Heat Exchanger Vaillant VMW 226/3-3 (Giannoni GM30-45-004-09) Ref. GM30-45-004-09

Stock · 1 unit

Refurbished combustion chamber assembly with primary condensing heat exchanger for Vaillant ecoTEC pro VMW 226/3-3. Manufactured by Giannoni (GM30-45-004-09) and equivalent to OEM Vaillant 0020135129 (replaces 0020018181). Its function is to transfer heat and condense the flue gases, affecting the start-up, efficiency, and safety of the equipment.

VAT included

Compatibility

Vaillant boilers compatible with reference GM30-45-004-09

Combustion chambers with reference GM30-45-004-09. A proven compatibility: VMW 226/3-3.

Proven compatibility

Boiler modelFamilyVerification
Vaillant VMW 226/3-3ecoTEC proContrasted

Can't see your model or have questions? The printed reference takes precedence. How to check it ·

Guide

How to check if the reference GM30-45-004-09 is the part for your boiler.

What determines it is not the boiler model, but the reference printed on the part you already have installed.

Diagnosis and fault codes

Symptoms and faults that the GM30-45-004-09 combustion chambers solve.

Common symptoms and faults

  • 01

    Intermittent lockouts F.28/F.29 after several attempts

    Cause: Recirculation of gases or condensate in the chamber due to obstruction in the passages of the heat exchanger or siphon.

    Inspect siphon/drain; check flue/air intake; observe moisture/frost inside chamber; measure flame stability.

  • 02

    F.25 with correct ventilation and flue.

    Cause: Smoke side passages of the heat exchanger dirty/deformed

    Measure flue gas temperature; check back pressure; visual inspection of the bundle; assess chemical/mechanical cleaning.

  • 03

    F.20/F.23 with a very high ΔT supply/return

    Cause: Hydraulic blockage of the primary circuit due to sludge/incrustation

    Check the pump flow and filters; perform flushing/cleaning; if the abnormal ΔT persists, primary defective.

  • 04

    Condensate dripping/trace on the chamber base

    Cause: Internal leak of the heat exchanger to the combustion chamber

    Hydraulic tightness test of the primary with sealed points; presence of white deposits/oxides in the chamber.

  • 05

    Smell of combustion and marks on the sight glass

    Cause: Recirculation through partially blocked flue passages

    Check the integrity of the flange gasket, the condition of the burner, and the cleaning of the fins on the body.

Fault codes from Vaillant that this part resolves.

CodeFaultDiagnosis and solution
F.28Start-up fault: ignition failedCheck gas valve/gas pressure, electrodes/ignition, and grounding. Also, inspect the intake pipe and condensate drain for obstruction. Relationship: condensate in the chamber or blockage/re-circulation of flue gases within the body can prevent ignition and may require replacement if there is damage/corrosion in the assembly.
F.29Flame loss; failed ignition retryIn addition to gas and mass, check the exhaust/admission and condensate discharge. Relationship: accumulation of condensate in the chamber or recirculation due to blocked passages in the heat exchanger can extinguish the flame; if it persists after cleaning/adjustments, consider replacing the body.
F.25Combustion gas temperature too highCheck the gas flow (obstruction, wind), internal bleeding, flow rate, and fan. Relationship: dirty/deformed fins/passages of the heat exchanger raise the flue gas temperature; if cleaning does not restore values, the heat exchanger may be damaged.
F.20Disconnection due to temperature limiter (STB)Check NTC, bleeding and flow rate. Relationship: internal blockage of the primary (sludge/incrustation) reduces flow rate, triggers STB; if the flushing/hydraulic cleaning does not resolve, replace the primary.
F.23Excessive temperature differential; insufficient flowCheck the pump, air in the circuit, hydraulic filter, pressure sensor. Relationship: hydraulic throttling within the heat exchanger increases ΔT supply/return; rule out with cleaning and, if it persists, replace the body.

These symptoms can have more than one cause. If your boiler displays a fault code, send it to us via WhatsApp along with a photo of the labeling, and we'll tell you if this is the part.

Technical data

Data sheet for the combustion chambers Vaillant GM30-45-004-09

Catalogue reference
GM30-45-004-09
Brand
Vaillant
Type of part
Combustion chambers
Units in stock
1 unit
Status
Refurbished
Warranty
1 year
Shipping
1-2 business days
Return
14 days

Data read on the part and in the manufacturer's documentation

What we have not been able to verify does not appear here.

Type of part
Combustion chamber with primary condensing heat exchanger
Boiler brand
Vaillant ecoTEC pro VMW 226/3-3
Component manufacturer
Giannoni
Component model
GM30-45-004-09
equivalent OEM Vaillant
0020135129 (replaces 0020018181)
Primary material
Stainless steel
Key functions
Primary heat exchanger, sealed combustion chamber, condensation, and condensate drainage.
Before purchasing
  • Cut off gas and electrical supply before intervening.
  • Wait for complete cooling; risk of burns.
  • Mandatory bleeding of the circuit (program P.0) after any opening.
  • Use new single-use gaskets in the flange/chamber and seals resistant to condensates.
  • Check the gas tightness and the flue gas circuit after installation.
  • Check and, if necessary, adjust combustion (CO₂) according to the manual.
  • Torque: apply the one specified by Vaillant in the model's manual.
  • Check the free drainage of the condensate siphon after the intervention.
Frequently Asked Questions

Frequently asked questions about the combustion chambers GM30-45-004-09.

Is it compatible with my VMW 226/3-3 if my original heat exchanger is 0020018181?
Yes. Vaillant documents 0020135129 as a replacement for 0020018181; the Giannoni GM30-45-004-09 body corresponds to that assembly. Always confirm by checking the component's label and the parts list of your unit.
Does it include a fan, electrodes, or a gas valve?
No. This set refers to the Giannoni body (chamber + heat exchanger). The peripherals are either kept or replaced separately based on diagnosis.
After changing the heat exchanger, does the boiler need to be configured?
There is no coding for the heat exchanger, but it should perform bleeding P.0 and combustion verification (CO₂). Clear faults and check operation at minimum/maximum load according to the manual.

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Combustion Chamber + Heat Exchanger Vaillant VMW 226/3-3 (Giannoni GM30-45-004-09) Ref. GM30-45-004-09