Home boiler issues

treehouse15

Hi everyone,

We live in a house. Our boiler provides hot water for our use (in kitchen and bathroom). Also it heats the house (through radiator).

For the last few days, there are episodes where our boiler is not able to heat the water for our use (shower, kitchen etc.). These episodes are temporary. The rest of the time, the boiler is working fine. When these episodes happened, I would look at the boiler, and the blue light would be flashing (when the boiler is working normal, the this light is green all the time, and not flashing/blinking).

A couple of times, I clicked on the reset button, and the boiler started working right away. One time, I just waited for a few minutes without doing anything, and the boiler started working after a few minutes. The brand of our boiler is Vaillant.

What do you think? What is wrong?
I appreciate everyone's feedback.
Thanks 

treehouse15

Here is the picture. Right now the boiler is working fine.

treehouse15

As you can see, the display is showing the water temperature 51 degrees, which is what we want. Last night, when one of these episodes was happening, the display was showing the water temperature as 25 degrees, and the green light under the display was blinking.

treehouse15

In the first post I mentioned blue light flashing/blinking. I meant green light. There is no blue light 

Mr.Generous

What does the pressure gauge show when the boiler stops working?

Farway

Bottom right-hand dial. Is that water pressure?

Look in your user instructions and check if it is too low.

I know when mine drops the boiler will not fire, maybe yours does the same?

treehouse15

Thank you for your responses.
The water pressure stays the same. I looked at the user instructions, and it seems that the water pressure is adequate.

molerat

Could be any of a thousand and one things.  Does the screen not give a code ?

treehouse15

No. The screen doesn't give any code when these episodes are happening. It just shows low water temperature (for example 25 degrees).

EssexHebridean

When was it last serviced? If that's due before too long, might be a plan to get it booked in sooner rather than later. 

grn99

Sounds like a possible problem with the diverter valve.Probably best to get an engineer out.