biasi m90e.24s problem

[vanders]

Hello to everyone on DIYnot.
I seem to be having trouble with my biasi boiler. I have noticed that the temperature of the hot water keeps dropping out when i use the shower. The boiler will work fine initialy but then cut out a fire up again. The radiators also heat up when the shower is being used. Having looked at the manual i am thinking that the Three way diverter valve is the problem but im not 100% sure. Any advice would be greatly appreciated.
Many Thanks

Lee

 

[gas4you]

Sounds like the DV is stuck mid position.

I would replace it.

You may also have a blocked plate he. Whilst boiler drained down I would suggest removing it and cleaning.

 

[vanders]

Thanks for your advive dave.
I have cleaned the HE. A load of black gunk came out of that, must have built up over the months/years that its been installed.

As for the DV, Do i change the whole thing or just the valve itself??
I've tried to get the nuts open both ends and they are stiff to say the least.

Kind regards

Lee

 

[gas4you]

Has the hot/cold fault stopped since cleaning the plate? Did you use a strong cleaner such as DS40 or even DS3?

Plain water will not clean it properly.

The main 'nuts' should come undone with the right wrench/grips and a bit of persuasion

 

[vanders]

I just used plain water and it has done the trick, but for how long is another matter.

If/When it goes again then i'll get some of the DS40 that you mentioned

Thanks for your help mate!!