Transformer Vaillant VC 240 / VCM 242 E and Compatible Models
When you open the hot water tap or turn on the heating, the Vaillant VC 240 / VCM 242 E transformer is responsible for generating the spark needed to ignite the burner. If this part fails, you will notice that the boiler attempts to start unsuccessfully, showing symptoms such as fault code F.28, where it fails to ignite the burner, or fault code F.29, if the flame goes out during operation. This transformer is compatible with Vaillant boilers from the Turbo Tec, Atmo Tec ranges and VC models, among others. A technician must confirm through diagnosis whether it needs to be replaced when these ignition faults are observed.
- Type of part
- Transformers
- Status
- Refurbished
- Catalogue reference
- 287450
- Warranty
- 1 year
Vaillant boilers compatible with reference 287450
Ignition transformer with reference 287450. 12 verified compatibilities: VMW ES 242/3 and VMW 242-3.
Proven compatibility
| Boiler model | Family | Verification |
|---|---|---|
| Vaillant VMW ES 242/3 | Vaillant Turbo Tec / Turbo Pro (VMW) | Contrasted |
| Vaillant VMW 242-3 | Vaillant Turbo Tec / Turbo Pro (VMW) | Contrasted |
| Vaillant VMW 242-5 | Vaillant Turbo Tec / Turbo Pro (VMW) | Contrasted |
| Vaillant VMW 240-5 | Vaillant Turbo Tec / Turbo Pro (VMW) | Contrasted |
| Vaillant VMW 282-5 | Vaillant Turbo Tec / Turbo Pro (VMW) | Contrasted |
| Vaillant VM 242-5 | Vaillant Atmo Tec / VM (heating only) | Contrasted |
| Vaillant VM 282-5 | Vaillant Atmo Tec / VM (heating only) | Contrasted |
| Vaillant VC 242 E | Vaillant VC / VCM (combi-compact) | Contrasted |
| Vaillant VCM 242 E | Vaillant VC / VCM (combi-compact) | Contrasted |
| Vaillant VCM 282 E | Vaillant VC / VCM (combi-compact) | Contrasted |
| Vaillant VMI 280-7 | Vaillant VMI | Contrasted |
| Vaillant VMI 282-7 | Vaillant VMI | 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. 287450 is the part for your boiler
The part reference, model, and equipment revision must be verified against the manufacturer's documentation.
- Find the reference printed on the installed part and check whether it matches the catalogue reference 287450. 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 that require diagnosis in the ignition transformer 287450
The ignition transformer generates the high voltage for the spark of the electrodes. These are the typical symptoms and what to do:
Common symptoms and faults
- 01
The boiler works intermittently: sometimes it turns on and other times it just stays dead.
Cause: An internal contact of the transformer fails intermittently, leaving the electronics without voltage irregularly.
Gently tap the casing near the transformer while measuring the secondary voltage to see if the fault is mechanical.
- 02
The fuse blows as soon as the boiler is turned on.
Cause: A short circuit in any load on the secondary side triggers the protection almost instantly.
Disconnect the secondary connector and measure the fuse separately before considering the transformer as faulty; this way you isolate if the problem comes from afterwards.
- 03
The boiler starts but immediately locks out with a fault code related to electronics or communication.
Cause: A secondary voltage below normal does not stabilize the PCB and it locks out for safety.
Measure the secondary voltage with the boiler running, not just at rest; a drop under load points to the transformer.
- 04
The fault appeared right after a storm or a power outage with flickering.
Cause: Low-power transformers do not always absorb voltage spikes from the grid well, and the primary winding can burn out without warning.
Check with the multimeter if there is continuity in the primary winding; if it is broken, also inspect the rest of the home's electrical installation.
Vaillant fault codes that require diagnosis
| Code | Fault | Technical checks |
|---|---|---|
| F.28 | Fault during start-up: the boiler fails to ignite the burner in the start-up phase. | The ignition transformer is part of the ignition system (transformer + cable + electrode); if the transformer fails, it does not generate the high voltage for the spark, and the boiler aborts the start-up without detecting a flame. Verify: measure the transformer's output voltage to the electrode and check for a spark at each start-up; if there is no spark and the wiring/electrode are fine, the transformer is the cause. |
| F.29 | The flame goes out during operation and re-ignition attempts fail. | The Vaillant service documentation explicitly lists "the ignition transformer has a spark fault" as the cause of F.29: if the transformer does not reignite after a flame failure, the lockout is triggered. Verify: check the spark generation of the transformer during ignition retries and rule out poor grounding, gas pressure, and condensate pipe before. |
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.
Vaillant 287450 ignition transformer datasheet
- Catalogue reference
- 287450
- Uniclima internal SKU
- TVCMES180X
- Brand
- Vaillant
- Type of part
- Transformers
- Units in stock
- 3 units
- Status
- Refurbished
- Warranty
- 1 year
- Shipping
- Delivery time shown at checkout
- Return
- 14 days
Part data and available documentation
Contrast the label codes, PCB, and revision with the installed part; they are not necessarily equivalent references.
- Primary voltage
- 230 V
- Frequency
- 50/60 Hz
- Secondary voltage
- 17 V
- Apparent power
- 18.4 VA
- Fuse
- 1.25 AT
- Thermal class
- ts70/B
- Core
- EI60
Frequently asked questions about the ignition transformer 287450
Does this transformer work for the Vaillant VUW 282?
What fuse does the transformer compatible with the Vaillant VC 240 use?
What thermal class does this transformer have for the Aqua Plus VUI 362-7?
What primary voltage does the Vaillant VM 242-5 need for this transformer?
How many models are compatible with the Vaillant TVCMES180X transformer?
What fault codes are documented for this transformer?
Spare parts related to Vaillant Turbo Tec / Turbo Pro (VMW)
