Vaillant Boiler Fault Codes

5,673 fault codes across 61 Vaillant boiler models — explained in plain English.

Premium German heating manufacturer with over 140 years of experience. Popular in UK social housing and new builds.

5,673 fault codes
61 models documented
20 currently sold
41 legacy models
Just want the most common Vaillant problems?
The top 8 faults across the whole Vaillant range — causes, DIY checks, repair costs.
Most serious

High-severity Vaillant fault codes

F.00
Your boiler has lost connection with its internal temperature sensor, meaning it cannot monitor heat levels and has shut down as a safety precaution.
Turbomax Plus 824/828E
 F.01
Your boiler has stopped working because a sensor that monitors water temperature has lost its connection or stopped sending a signal.
Turbomax Plus 824/828E
 F.10
Your boiler has detected a loose connection or a fault with the sensor that monitors the temperature of the water returning to the unit.
Turbomax Plus 824/828E
 F.13
Your boiler has detected an electrical short circuit in its internal temperature sensor, causing the system to shut down for safety.
Turbomax Plus 824/828E
 F.20
Your boiler has switched itself off because it has become too hot internally and needs time to cool down before it can be used again.
Turbomax Plus 824/828E
All models

61 Vaillant boiler models

Turbomax Plus 824/828E
Combi Discontinued
59 fault codes · 2001-2006
ecoTEC 65kW
System Discontinued
14 fault codes · 2006-2018
ecoTEC Pro / ecoTEC Plus
CombiSystemRegular
72 fault codes · 2005-present
ecoTEC plus Regular
Regular
117 fault codes · 2012-present
ecoTEC plus
CombiSystemRegular
171 fault codes · 2005-present
ecoTEC
CombiSystemRegular
137 fault codes · 2005-present
ecoMAX
CombiSystem Discontinued
36 fault codes · 2001-2006
ecoTEC exclusive
CombiSystem
157 fault codes · 2016-present
ecoTEC Pro
Combi
90 fault codes · 2012-present
Thermocompact
System Discontinued
82 fault codes · 1995-2005
Turbomax Pro 28 2E
Combi Discontinued
18 fault codes · 2000-2002
Turbomax VUW 242/1
Combi Discontinued
5 fault codes · 1997-2001
ecoFIT Pure 825
Combi
49 fault codes · 2016-present
ecoFIT Pure 830
Combi
52 fault codes · 2016-present
ecoFIT Pure 835
Combi
97 fault codes · 2017-present
ecoFIT Pure 412
Regular
81 fault codes · 2017-present
ecoFIT Pure 418
Regular
97 fault codes · 2017-present
ecoFIT Pure 425
Regular
97 fault codes · 2017-present
ecoFIT Pure 435
Regular
97 fault codes · 2017-present
ecoTEC sustain
Combi
171 fault codes · 2019-present
ecoTEC Pro 24
Combi
90 fault codes · 2006-present
ecoTEC Pro 28
Combi Discontinued
90 fault codes · 2012-2023
ecoTEC Pro 30
Combi
84 fault codes · 2006-present
ecoTEC Plus 610
System Discontinued
39 fault codes · 2006-2012
ecoTEC Plus 615
System Discontinued
171 fault codes
ecoTEC Plus 620
System Discontinued
171 fault codes · 2006-2020
ecoTEC Plus 625
System Discontinued
171 fault codes · 2006-2020
ecoTEC Plus 630
System Discontinued
171 fault codes · 2006-2020
ecoTEC Plus 635
System Discontinued
171 fault codes · 2012-2020
ecoTEC Plus 826
Combi Discontinued
46 fault codes · 2006-2012
ecoTEC Plus 832
Combi Discontinued
171 fault codes · 2012-2023
ecoTEC Plus 836
Combi Discontinued
171 fault codes · 2012-2022
ecoTEC Plus 840
Combi Discontinued
171 fault codes · 2006-2012
ecoTEC Plus 65
System
171 fault codes · 2016-present
ecoTEC Plus 938
Combi Discontinued
171 fault codes · 2012-2020
ecoMAX 613
System Discontinued
66 fault codes · 2000-2005
ecoMAX 618
System Discontinued
66 fault codes · 2000-2005
ecoMAX 622
System Discontinued
66 fault codes · 2000-2005
ecoMAX 635
System Discontinued
66 fault codes · 2000-2005
ecoMAX Pro 18E
System Discontinued
17 fault codes
ecoMAX Pro 28E
Combi Discontinued
47 fault codes · 2000-2005
ecoMAX System 612
System Discontinued
66 fault codes · 2000-2005
ecoMAX 824E
Combi Discontinued
66 fault codes · 2000-2005
ecoMAX 828E
Combi Discontinued
66 fault codes · 2002-2006
Turbomax Plus VUW 242E
Combi Discontinued
59 fault codes · 2000-2005
Turbomax Plus 828 E
Combi Discontinued
59 fault codes · 2000-2005
Turbomax Plus VUW 242EH
Combi Discontinued
59 fault codes · 2000-2005
Turbomax Plus 828
Combi Discontinued
58 fault codes · 2000-2005
Turbomax 824/828
Combi Discontinued
1 fault codes · 1997-2005
Turbomax VU 182
Regular Discontinued
6 fault codes · 1997-2006
Turbomax VU 242
Regular Discontinued
1 fault codes · 1997-2005
Turbomax VU 282
System Discontinued
6 fault codes · 1997-2004
Atmomax
Combi Discontinued
164 fault codes · 2000-2010
Combi Compact 242EB
Combi Discontinued
164 fault codes · 1994-2001
Combi Compact 282EB
Combi Discontinued
164 fault codes · 1994-2002
ecoTEC plus Aquaplus
Combi Discontinued
94 fault codes · 2006-2012
ecoTEC plus System
System
137 fault codes · 2012-present
ecoFIT pure
Combi
97 fault codes · 2017-present
Ecomax Condensing 600/800 series
CombiSystem Discontinued
89 fault codes · 2003-2007
aquaPLUS
Combi Discontinued
94 fault codes · 2003-2009
Home System
System
137 fault codes · 2015-present