
Vaillant Gas Valve VMW 306/5-5
In the Vaillant EcoTec Plus VMW boilers, the gas valve VMW 306/5-5 regulates the flow of gas to the burner according to the commands from the control board. When this valve fails, the boiler may not ignite, experience flame lockouts, or have modulation issues. Users may notice faults such as F.28, F.29, F.61, or F.62 during operation. This model is compatible with other models in the EcoTec Plus VMW and VM range, such as the VMW 246/5-5 and the VM 306/5-5, among others. It should be replaced when these symptoms or faults occur in the system.
VAT included
Consult via WhatsAppVaillant boilers compatible with reference 0020146733
Gas valve with reference 0020146733. Six confirmed compatibilities: VMW 246/5-5 and VMW 306/5-5.
Proven compatibility
| Boiler model | Family | Verification |
|---|---|---|
| Vaillant VMW 246/5-5 | EcoTec Plus VMW (combi) | Contrasted |
| Vaillant VMW 306/5-5 | EcoTec Plus VMW (combi) | Contrasted |
| Vaillant VMW 346/5-5 | EcoTec Plus VMW (combi) | Contrasted |
| Vaillant VM 246/5-5 | EcoTec Plus VM (heating only) | Contrasted |
| Vaillant VM 306/5-5 | EcoTec Plus VM (heating only) | Contrasted |
| Vaillant VM 346/5-5 | EcoTec Plus VM (heating only) | Contrasted |
Can't see your model or have questions? The printed reference takes precedence. How to check it · Send us a photo via WhatsApp.
How to check if ref. 0020146733 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.
- Find the reference printed on the installed part and check whether it matches the catalogue reference 0020146733. If it is not visible, do not identify the part from its shape alone.
- Check the full boiler model on its data plate and look for it in the model associations on this page.
- Compare the connections and physical body with the original part before installation.
- If anything is unclear, send us a photo of the marking via WhatsApp before placing your order.
Symptoms and faults that the gas valve 0020146733 resolves.
The gas valve regulates and modulates the gas flow to the burner. These are the typical symptoms and what to do:
Common symptoms and faults
- 01
The boiler does not ignite, although the spark can be heard and the fan is functioning normally.
Cause: The coil does not generate the magnetic field necessary to open the gas valve, so gas does not reach the burner.
Before replacing it, check with a multimeter that the coil has continuity and that it receives voltage at the moment of ignition.
- 02
The burner turns off by itself during operation, for no apparent reason.
Cause: The coil may lose strength when heated and stop keeping the gas valve open, cutting off the gas abruptly.
Check if the cut occurs only when the boiler has been running for a while: if it also happens when cold, suspect another component first.
- 03
There is a slight burnt smell in the area of the gas valve.
Cause: A damaged coil can overheat and affect the proper closure of the gas valve assembly.
Visually check if the coil or its connector show signs of heat damage or a burnt plastic smell before replacing it.
Fault codes from Vaillant that this part resolves.
| Code | Fault | Diagnosis and solution |
|---|---|---|
| F.28 | Start-up fault: ignition failed | If THIS gas valve (0020146733) does not open or is misadjusted (offset/calibration), insufficient gas reaches the burner during ignition. Check voltage/control at the connector, adjustment of the gas block, and pressures at test points during the ignition test. |
| F.29 | Ignition and control error during operation, the flame is off. | A faulty or poorly modulated gas valve can cut off or fail to stabilise the flow, causing the flame to extinguish during operation. Check modulation/control voltage during operation and the adjustment/offset and pressure at the gas test point. |
| F.61 | Gas valve activation error | The coil/actuator of THIS valve is open/short-circuited or not receiving the command from the PCB, preventing its opening/closing. Check coil continuity/ohmage, command voltage, and harness/connector to the valve assembly. |
| F.62 | Gas valve disconnection delay | Delayed closure or internal leak in THIS valve causes the flame signal to persist after the shutdown command. Check the tightness of the assembly and ensure that the pressure at the burner connection drops to zero when the demand is cut (and immediate cessation of ionisation). |
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.
Data sheet for the gas valve Vaillant 0020146733
- Catalogue reference
- 0020146733
- Brand
- Vaillant
- Type of part
- Gas valves
- 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.
- Connection diameter
- 8 mm
- Degree of protection
- IP30
- Working temperature range
- -15°C to +70°C
Manuals and technical documentation
Official documentation of the boiler, useful for locating the part and cross-referencing the fault codes.
- Vaillant VMW 346/5-5 Manual (PDF)Document © Vaillant, provided as a technical reference.









