CH stays on even though timer is set off

[GNServices]

Hello,

I have a problem with a Valliant Ecomax 824/2E boiler.

The central heating on the boiler comes on even though the timer says OFF, the timer is wired as according to the boiler manual. I've even tested its not the timers fault by unplugging the cables which would signal the boiler to come on.

When the CH comes on (when timer is set OFF), even if i turn the CH temperature dial all the way down, it continues to heat.
No fault codes seem to come up and the "status" doesn't seem to show anything odd.

Any ideas??

 

[Dan Robinson]

and the "status" doesn't seem to show anything odd.

But what does the status show?

 

[GNServices]

and the "status" doesn't seem to show anything odd.

But what does the status show?

I don't recall the exact numbers but it says something like s.23 then s.24
which is ignition sequence warm start, then burner ignited.

What I mean about "anything odd" is that it doesn't say s.34 for instance, aka frost protection mode.

I must note, that when the boiler does come on without prompt from the timer,
The temperature displayed on the LCD display increases pretty rapidly and after 5mins or so, the flame turns off (I cant note any status numbers at this point). When it does this, If i remember correctly, the pump is on.

When the timer is operated, and CH set to ON, the CH will come on, and the temperature will increase slowly (as you would expect), and the flame will turn off if the temperature dial on the boiler is turned down (as expected)

 

[Dan Robinson]

Guffed diverter valve causing the warmstart to keep kicking in.


Or perhaps a guffed diverter valve and a drippy tap acting together.

 

[GNServices]

Guffed diverter valve causing the warmstart to keep kicking in.


Or perhaps a guffed diverter valve and a drippy tap acting together.

No drippy taps from what I can see, however I will not rule it out (for now), Id imagine you'd need a very drippy tap to give the boiler the impression you need the heat to come on? (The HW symbol or whatever has not came on the display when the heat comes on unexpectedly).

I'm a newbie when it comes to boilers, please explain how the diverter valve would make the boiler turn on. (would this also explain temperature increasing fast?)

How can the diverter valve be checked to be okay or not?
Can it be stripped, greased and put back together?

Thanks

 

[Dan Robinson]

If the warmstart is calling for heat, but the diverter valve is guffed, then the the being generated is being sent down the heating rather than to the domestic heat exchanger (to satisfy the warmstart sensor).



This is based in the hypothesis that the boiler thinks it is doing warmstart.

 

[GNServices]

If the warmstart is calling for heat, but the diverter valve is guffed, then the the being generated is being sent down the heating rather than to the domestic heat exchanger (to satisfy the warmstart sensor).



This is based in the hypothesis that the boiler thinks it is doing warmstart.

So what should I do?

I forgot the mention at the start, the boiler has been standing (not ran at all) for atleast 5/6 months.

 

[Dan Robinson]

Check the diverter valve.

 

[mogget]

Check the diverter valve.

 

[GNServices]

Check the diverter valve.

How do I check/test Haha