Vaillant Plus 831 boiler F32 error code


Someone please help me on an issue, which my seven years Vaillant plus 831 boiler is having now days. Whenever I turn on the boiler, it starts displaying a F32 error code. I do not have any idea behind the exact the reason behind it. Therefore, please share your views

Thanks in advance


Hi Rob,

This error code deals with the air fault in your boiler. In Vaillant plus 831 boiler, there are two major reasons behind the air fault i.e. the faulty fan or the faulty flue. Firstly, by doing the quick visual examination, you can confirm that either the boiler’s flue is chocker or not. Generally, the fan is a culprit. It can be the minor problem for instance, the rotation speed of the fan is not correct. Nevertheless, old fans always deteriorate quickly. In short, if the fan is faulty then you have to replace it immediately.

Vaillant Thermocompact boiler control board issue

Hello Everyone,

I have bought my Vaillant Thermocompact boiler around five years ago. It is working well expect that when the cylinder stat or room stat shuts off the gas, a demand light remains to spark & pump is running as well. I have replaced the main control board. Now what should I do?

Thanks a lot


Hi Allen,

The boiler’s central heating pump should run long especially when the gas shuts off due to the residual heat. Moreover, it is better to shut off the gas all of a sudden & try to run off the retained heat. I hope that this will solve your problem. In case the problem persists, do call a Vaillant boiler engineer for in-depth investigation.

Vaillant Turbomax boiler fault code F20

Hi Guys,

My newly bought and installed Vaillant Turbomax boiler is displaying a F20 error code. I tried my best to fix at home after reading the Vaillant boiler’s user manual but unluckily no positive outcome. If someone has faced this issue then please help me.



Hi Tom, the F20 error code on the Vaillant Turbomax signifies an issue with a boiler overheating. I would like to share that the boiler has the device named as NTC thermistors. The purpose of these devices is to monitor the temperature of the water out & into the boiler. If the water temperature is very high, the boiler will go into lockout state because of overheating. The basic reason behind it is a low pressure of boiler due to lack of the water in your boiler.

Vaillant boiler dripping water just when heating is switched off

Hello Folks,

Can someone help & identify an issue on my six years old Vaillant boiler. The boiler worked quite well until warrantee ran out. Few days before, after turning off the heating I have observed that boiler is dripping constantly underneath. For getting the desired hot water, I have to top up the boiler’s pressure. The leak would rarely stops for few hours & afterwards again same issue. Should I replace the boiler?

Thanks for your suggestions


Hi Ben,

I think the joint has become a little loose from a cooling cycle and heating. You have to put the leak pan under the dripping range (the leaks would evaporate rapidly), then whenever you shut it down always go through the different joints/connections in a range with wrenches for finding the unfastened joint.

Vaillant Combi boiler not firing up

Hi All,

I have purchased the Vaillant Combi boiler five years ago. My problem is, a boiler is not firing up although its pilot light is set alight. Moreover, the pressure of the boiler is fine & the heating pump is heard running. What should I do in order to fix the problem?

Looking for the Help


Hi Harry, first of all check the ignition socket either it is working properly or not. Upon switching on the boiler, the spark will generally activate the firing. Afterwards, check an ignition convertor if it is working or not. Now, check the secondary current, which is about 15000-20000 volts for trigging the ignition socket & your boiler to easily fire up. In case, there is no spark, you have to replace the ignition converter in order to make your boiler work again.

Vaillant Turbomax boiler fault code F28

Hello Guys,

My two years old Vaillant Turbomax boiler is constantly showing a fault code i.e. F28. In order to get rid it of, I have turned off the boiler. After 1 or 2 hour, I switched it on but again the same issue. Someone please tell the ways of addressing this issue.



Hi Euan,

This problem is quite common in majority of the Vaillant Turbomax & usually caused by the faulty ignition. For fixing it, firstly, check the ignition’s leads current condition like is the spark being produced. In case not, you have to replace them as it might fix the issue. If you notice the spark, do check the power, which is going to the gas control device. Afterwards, check if the gas is easily flowing through. In case, gas valve has the power but the gas is not flowing, it might need replacement.

Vaillant boiler during windy season the flame goes out

Hi Everyone,

Someone please help me regarding an issue, which my boiler faces when it is windy out there. Basically, the boiler’s flame always keeps going out especially whenever it is stormy outside. What should I do?

Thanks for your suggestions


Well, Rich, it is quite rare that your boiler faces this issue just because of the wind. Nevertheless, sometimes this is a case & generally caused by the wrong installation of flue. Normally, the wind does not cause the flame to blow out. When your boiler identifies an imbalance gas pressure of the flue, it will surely lockout. A minor gust of the wind will change the current pressure in a flue & therefore, causes a lockout. On the other hand, the boiler’s fan is faulty. The absence of the light wind being generated by the fan can be a culprit.

Vaillant boiler F27 fault

Hello Everyone,

My newly bought Vaillant boiler is showing a F27 error code since last night. I have tried to fix the issue after reading the user manual but I guess I am lacking somewhere. Someone please help me to fix the problem.



Hi Ray, I would like to mention that your Vaillant boiler is showing up the F27 error code due to several reasons such as:

  • The boiler’s PCB is having an issue or not working properly
  • The defective flame sensor
  • The faulty gas valve

The F27 fault is definitely not as easy & simple to troubleshoot. The proficient Vaillant boiler engineer will has to come for inspecting your boiler & its internal parts in order to diagnose the exact problem.

Vaillant Plus 831 lukewarm water issue

Hi All,

I bought & installed the Vaillant plus 831 boiler one year ago. Well, now days, the boiler is having an issue of supplying lukewarm hot water from showers & taps. I have tried to fix it but no success. I sincerely need the suggestions of all those who have faced this issue earlier.

Thank you so much


Hi William, getting the lukewarm hot water from the taps & showers is the most common sign of the damaged diverter valve. You boiler is supposed to prioritize the hot water however, if the diverter valve is little held open especially on a heating side then, it is important to note that some of heating power is on the run which is normally supplied to your showers & taps. I never recommend trying to repair your boiler at home instead call the skilled boiler engineer.

Vaillant boiler error code F75

Hello Guys,

I have bought and installed my Vaillant boiler five years ago. Overall, I am satisfied with the performance of the boiler. Moreover, I have not faced any kind of severe issue but from last two days, the boiler is displaying a F75 error code. I tried restarting the boiler several times but fortunately, the problem persists. What should I do?

Thanks in advance


Hi Bill,

The fault code F75 is considered as the most common issue among Vaillant boilers. The F75 fault code deals with the following errors according to the boiler’s user manual:

  • Faulty pressure sensor
  • Faulty central heating pump
  • Or sometimes both

In order to diagnose the existing fault in a better way, you should call a Vaillant boiler engineer.