Biasi M96 28 Combi boiler water is not getting much hot


I own a four years old Biasi M96 28 combi boiler. It worked perfectly but from the last few days, I am not getting the required hot water. Sometimes, the water only gets hot when I turn on the heating. What could be the possible reason behind it?

Please help me by giving your suggestions

Thanks in advance


Hi Craig,

This fault in your boiler is most likely relates to the faulty diverter valve. A diverter valve is considered as an important part of the boiler. Well, coming towards your problem, sometimes there is no need to replace the entire diverter valve because the problem generally lies with a washer on a diaphragm. Nevertheless, the entire cost of the labor especially to disassemble & reassemble your boiler simply means that it is better to replace a whole diverter valve.

Biasi M90 Combi Boiler fan cycling off and on

Hi All,

My newly installed Biasi M90 Combi boiler makes a loud whirring noise for about three seconds before firing up. It is a quite annoying thing. Has someone faced this issue earlier if yes, and then please tell me how I can fix it?

Thanks a lot


Hi Ben,

I think the fan in your boiler is not working properly. Like some other boilers, we can narrow down the fan faults on your Biasi combi boiler into the following:

  1. Damage or loose connections/wirings
  2. A faulty printed circuit board
  3. Defective air pressure switch

You have to call a boiler engineer, as he will determine where a fault lies within the:

  1. Wiring
  2. Air pressure button
  3. Printed circuit board
  4. Fan

Sometimes, this issue can be fixed easily by just repairing the connections/wirings. On the other hand, in some cases, replacement parts are required

Biasi Combi Boiler no flame

Hello Guys,

My three years-old Biasi Combi boiler is facing an issue of no flame detection from last night. I have tried to fix it after reading the user manual but the problem persists. Someone please guide me that what should I do? Should I replace the boiler?



Hi Martin, there are various potential reasons behind it but most probably, it is due to a jammed pilot jet. Nevertheless, you cannot diagnose this problem easily. Therefore, do contact a Biasi boiler engineer & ask him to disassemble the boiler, clean the pilot jet & then reinstall it. Most importantly, he will check for something else which can affect the sequence of ignition & flame detecting abilities of the boiler.

Biasi Riva Compact HE boiler lockout

Hi Folks,

I have two-years-old Biasi Riva compact HE boiler. From last few days, I am noticing that hot water is going to excessive temperature. There is also a warning in the form of fault light. After all this, the boiler goes into a lockout state. I have restarted the boiler but all in vain. Does anyone have any knowledge regarding how to fix this issue?

Looking for the suggestions


Hi Alan,

I guess you should replace a thermostatic valve & put non-return regulators on cold and hot feed to shower. You are facing this issue due to an unexpected reason i.e. cold water is going into the line of hot water via the shower. You can contact a skilled Biasi engineer for additional help.

Biasi 24s Combi Boiler problem with ignition


I have a Biasi 24s combi boiler, which is now six years old. It worked well. However, now the boiler is having some minor issues like whenever I press a reset button the boiler catch fire for heating but, as I release this button, it just goes out. I do not know what is happening. I have restarted the boiler but no progress. Someone please guide me towards the right direction.

I shall be thankful to you



Hi Denis, it seems that you should replace the thermocouple or even adjust the old one. Well, it depends upon the current condition of thermocouple & boiler engineer can guide you after checking the thermocouple because, thermocouple is not holding a gas controller as it has to be.

Biasi M90 Combi boiler fan issue

Hi All,

I have a Biasi M90 combi boiler, which is nearly four years old. I have a problem with my boiler that is why I am here to get some suggestions. The fan and pilot light of the boiler do not seem to be working properly. Apart from this, I can hear the clear click as I turn on the tap of hot water & a clear click after turning off the tap. What could be the reason behind it?

Please give your valuable suggestions


Hi, try bleeding all the air from your boiler. Afterward, run heating and hot water at the same time. You have to bleed the central heating pump as well. Another possibility is to have air, especially in a pilot after switching it off. It is better to call a boiler engineer for detailed inspection of your boiler.

Biasi Combi Boiler produces deafening vibrating noise

Hello Everybody,

My newly bought and installed a Biasi combi boiler is producing a deafening vibrating noise & it is quite irritating. I am facing this issue from last two days. However, I would like to share that these sounds are periodic generally, happening just about a second after a Biasi boiler has tried to fire up successfully. Usually, it lasts for one minute. Someone please help me on urgent basis.



Hi Jess, 

According to the shared information, it looks as if there is a circulation issue nevertheless, bearing in mind the boiler’s age, I think there is some other problem such as an obstruction in the heat exchanger & combustion-related issue. If you think that there is a combustion related issue then, do call a boiler engineer and get it checked thoroughly. Well, I also have doubts that heat exchanger is blocked & due to this, there is some restriction. For this, power flushing is a highly recommended way out. Furthermore, I would advise power flushing the Biasi boiler on regular basis for preventing the sludge buildup & improving its performance.

Biasi Riva Compact HE boiler noisy pipes

Hi Guys,

My four years old Biasi Riva Compact boiler is making the strange banging sounds. I have checked the boiler in detail and concluded that these sounds are coming from the pipes. After numerous fruitless attempts at fixing this issue, I am using this platform to seek expert advice.

Thank you so much


Hi Rob, if one of the following condition is met then, you can face this issue especially when your Biasi boiler overheats a lot like:

  • Out of order thermostat
  • An accumulation of limescale or sludge
  • Blocked chimney
  • Water is not present in the right amount

In order to keep your boiler in better condition, it is advisable to get it serviced regularly. Another safe and recommended way is to contact a trained boiler engineer for further help

Biasi M90 Combi boiler no hot water but boiler is working

Hello Everybody,

I have installed and purchased the Biasi M90 Combi boiler five years ago. Throughout that period, I have faced some minor issues & fixed them successfully. However, from the last few days, the boiler is giving the tough time. The Biasi boiler is working properly but I am not having the hot water. What could be a possible reason behind it? Someone, please help



Hi William,

Figuring out that what is wrong especially when your boiler is working properly but you are unable to get the hot water is quite challenging. However, with a little patience and time, you can fix this issue. You have to check the following parts of the boiler:

  • The mechanical timer
  • A pilot light
  • An expansion tank and feed
  • Check for the frozen condensate pipes

If your problem persists, do call an experienced boiler engineer.

Biasi 24s Combi boiler incorrect water temperature

Hi Folks,

My two years old Biasi 24s boiler was working perfectly until last night, as now the water temperature of the boiler is not correct. Due to this, I am not getting the hot water in order to take shower or complete the household chores. How I can fix this issue? Any suggestions

Thanks in Advance


Hi James, firstly do check the boiler’s water portion and rate of gas as I guess that boiler is having an incorrect rate of gas & the water portion is wide of the mark as well. In order to fix the problem, check the supply of gas, which is going towards the boiler’s gas isolation regulator. For this, simply open the regulator while checking the inlet pressure & burner. If you noticed that water, segment of the water is wrong then, I would advise cleaning it instantly. Well, replacement is also recommended if it is severely damaged.