No hot water

[Tony 1]

Afternoon all.

I'm hoping someone can help as I've noticed that the water is not getting hot at all. I have a vaillant combi with a Tribune XE unvented water cyclinder controlled by a Danfoss TPOne-m but the pipe work isn't getting hot at all (circled in the photo) The system pressure is right but the boiler isn't even kicking in for the hot water. It's fine when central heating comes on.

Any ideas please?

 

[ianmcd]

Try opening that valve manually, slide the lever across and latch it open, then turn on one of the other circuits, and see if the water circuit now heats.

I have a vaillant combi with a Tribune XE unvented water cyclinder

That would be unusual but possible, are you sure it is a combi ?

 

[Tony 1]

Try opening that valve manually, slide the lever across and latch it open, then turn on one of the other circuits, and see if the water circuit now heats.



That would be unusual but possible, are you sure it is a combi ?

Yeah definitely a combi. That valve which I've ringed the pipe underneath it, there is no resistance on the lever at all, I can just wiggle it backwards and forwards unlike the other 2 valves which are the central heating circuit that have a resistance on the levers and you can hear the motors winding back

 

[dilalio]

Yeah definitely a combi

Is the cold inlet and hot outlet on the combi connected? Do you have a tap in kitchen /utility that still delivers hot water?

If you manually open the HW valve and latch it, then turn one of the heating zones on, you should feel HW going into the cylinder. You can also use the immersion to get you some hot water in short term.

Usually the HW MV needs changing.
Or at least Synchron motor.

Heating zone test above should confirm.

 

[Tony 1]

Is the cold inlet and hot outlet on the combi connected? Do you have a tap in kitchen /utility that still delivers hot water?

If you manually open the HW valve and latch it, then turn one of the heating zones on, you should feel HW going into the cylinder. You can also use the immersion to get you some hot water in short term.

Usually the HW MV needs changing.
Or at least Synchron motor.

Heating zone test above should confirm.

Now you've said that about the boiler I'm not 100% sure now. It looks as if theres a 1/2 inch gas supply going in at the bottom and then 2 x 22mm pipes coming out of the top which is the heating flow and return.

I can't manually open the HW valve at the cylinder as theres no resistance in the lever when pushing it to manual which is making me think the valve head is faulty?

When I put the heating on these circuits start getting hot which I've circled in yellow

 

[Johntheo5]

If you have the HW programmed OFF, is there now resistance when pulling that lever across?, if so then probably a faulty end switch so new valve head probably required. If you have a m.meter and the valve does open when HW only programmed ON and cylinder stat calling, you should get 230V between the grey wire and N (or earth) and 230V between the orange wire and N (or earth).

 

[Tony 1]

If you have the HW programmed OFF, is there now resistance when pulling that lever across?, if so then probably a faulty end switch so new valve head probably required. If you have a m.meter and the valve does open when HW only programmed ON and cylinder stat calling, you should get 230V between the grey wire and N (or earth) and 230V between the orange wire and N (or earth).

Everying is off and there's no resistance at all from pushing the lever, it doesn't even return back to auto when you let go of it like the other 2 do which you can hear the motorised valve closing on those. If I start running just the hot tap downstairs in the kitchen nothing happens and the HW valve appears to do nothing with both pipes circled in red remaining cold. The boiler doesn't even seem to be firing up but as soon as you turn the central heating on, the boiler kicks in and the rads start heating as normal. Got no faults showing on the boiler either. I'm at a loss to be honest now.

 

[Johntheo5]

Opening a hot tap will do nothing immediately even on a perfectly working system (non combi), the HW must be programmed ON and the cylinder stat must be calling for heat which it will eventually if you run off sufficient HW, if confident enough you should be able to remove the valve head and see if its that or the valve itself thats sticking open.

 

[Tony 1]

Opening a hot tap will do nothing immediately even on a perfectly working system (non combi), the HW must be programmed ON and the cylinder stat must be calling for heat which it will eventually if you run off sufficient HW, if confident enough you should be able to remove the valve head and see if its that or the valve itself thats sticking open.

Yeah the hot water is progam to be on permanently and there's no direct stat on the cylinder that I can see so I'm assuming it's called for via the Danfoss TPOne-m. I'll have a look at the HW valve tomorrow