What does the Viessmann E12 fault code mean?

Your boiler is most likely still heating your home and water, but it has lost its connection to Viessmann's online service, so remote monitoring and app control may not work until the link is restored.

How much does it cost to fix Viessmann error code E12?

Typical repair cost for the Viessmann E12 fault is £0-150 including labour.

Viessmann E12 Fault Code: What It Means & How to Fix It

What the manual says

Manufacturer manual

If "E12" is displayed, the connection to the server could not be established. Re-establish the connection at a later time.

From this model's manual

Verified against the Viessmann/Viessmann Vitodens 100 W B1hf B1kf 6167586 installation & service manual.

DIY fix possible

Check that your home Wi-Fi or broadband is working by loading a website on another device.Restart your router and wait about 5 minutes for it to reconnect fully.Switch the boiler off at its power supply or fused spur for about 1 minute, then switch it back on.Check that the boiler is within range of your Wi-Fi router, and that the Vitoconnect unit is firmly plugged in and its status light is on.Wait around 30 minutes, then check whether the E12 code has cleared. If it has not, contact a Viessmann-approved engineer or your heating company.

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All 151 fault codes on the Vitodens 100-W B1HF-19

Seeing a different code? Every code this model can display, in one place.

7 8 11 12 13 14 15 16 29 30 49 50 57 58 59 62 63 64 65 67 68 69 70 71 72 73 74 75 77 78 87 89 91 92 95 100 102 103 104 142 161 162 163 176 182 183 184 185 299 345 346 347 348 349 350 351 352 353 354 355 357 359 361 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 395 396 399 400 401 402 403 404 405 406 408 410 416 417 418 425 446 447 448 449 451 452 453 454 455 456 457 458 461 462 463 464 467 468 471 474 477 517 527 528 540 544 545 574 575 576 577 578 579 682 683 684 694 738 766 767 799 979 980 981 982 E10

Your boiler is most likely still heating your home and water, but it has lost its connection to Viessmann's online service, so remote monitoring and app control may not work until the link is restored.

What the manual says

DIY fix possible

Avoid the next call-out bill

All 151 fault codes on the Vitodens 100-W B1HF-19

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