Central heating not working as it used to be

When you say it doesn't work, is the boiler producing heat when only hot water is supposed to be on? You need to identify whether the issue is with the valve or elsewhere. The wiring (despite being a hideous mess of colours) does look OK to me (although some assumptions have been made about the stats and valve).

It seems likely that the boiler is doing what it is supposed to be doing but the valve isn't routing the water correctly to the cylinder.

With the wiring as it is and all components working, there's no reason your heating shouldn't work when the HW is off. Power comes from the programmer, out to the room stat, into the valve, out the valve when open to the boiler/pump.
 
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When you say it doesn't work, is the boiler producing heat when only hot water is supposed to be on? You need to identify whether the issue is with the valve or elsewhere. The wiring (despite being a hideous mess of colours) does look OK to me (although some assumptions have been made about the stats and valve).

It seems likely that the boiler is doing what it is supposed to be doing but the valve isn't routing the water correctly to the cylinder.

The valve was installed just 6 months ago whereas the one before that was replaced went for over 25 years. In fact I did not even need to replace it as my diagnosis of no hot water coming in shower was wrong and in fact the ballcock valve was faulty.

Yes the heating only coming after hot water is switched on. I have not tested other way yet where water is not heating on it's own without first putting heating to continuos mode.
 
When you just have heating on and hot water off, do you have heated water coming into the valve? I.E. is your boiler working when it's in this state?
 
When you just have heating on and hot water off, do you have heated water coming into the valve? I.E. is your boiler working when it's in this state?

Answer is No. I have to have both on to have the heating, only then heating comes on
 
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A faulty switch in the valve on the orange connection would explain heating only working when hot water is on. The valve is opening but isn't making the connection to call for heat from the boiler.

However, you said in the first post that you have to have the heating on in order to get hot water. It wouldn't explain that.
 
A faulty switch in the valve on the orange connection would explain heating only working when hot water is on. The valve is opening but isn't making the connection to call for heat from the boiler.

However, you said in the first post that you have to have the heating on in order to get hot water. It wouldn't explain that.
Actually I have to experiment with that (try that tomorrow) but definitely to get heating on I have to have hot water to on position.
 
Ok when turning hot water on by itself (without switching heating thermostat on) will start the boiler.

Therefore now we know hot water does not need heating on to work but heating to switch on does need hot water on,
 
Sounds like your valve isn't doing what it's supposed to then. Is it moving at all when there's a demand for heating or hot water?

For example, when hot water is on and heating is off, does the heating still heat up? If so, it'll be stuck in a position where both A and B are open at all times. If not, it's not physically stuck but when it opens for heating it's not making a connection to send live down your orange connection.
 
No heating will not come when water is just on, I tried doing that with turning up the room thermostat to no avail.
 
So it does sound like your valve is doing what it's supposed to do physically and closing when heating isn't required and just opening for HW. We know it opens for heating when heating is required too otherwise it wouldn't ever work. So, as I said, it sounds like your boiler isn't getting a call for heat through the valve when it is supposed to (orange wire).
 
So it does sound like your valve is doing what it's supposed to do physically and closing when heating isn't required and just opening for HW. We know it opens for heating when heating is required too otherwise it wouldn't ever work. So, as I said, it sounds like your boiler isn't getting a call for heat through the valve when it is supposed to (orange wire).

So what is needed, anything I can do to resolve this.

I am considering signing up for home service like home serve or 247homerescue. Do you think they can come and bring it back to normal, I know they include boiler service because it has not been serviced since its brand new installation about 8 years ago.
 
If you sign up with someone like Homeserve, they'll either want to inspect the system first or have an exclusion period where you can't make a claim.

You'd be best getting a plumber/heating engineer out to look at this specific issue and then getting cover for any future issues.

You probably need a new valve but to avoid wasting money if it's something else, get someone out to diagnose the fault in person and rectify.
 
I don't know because a new valve was installed just six months ago, unless I suspect the internal wiring has come loose of the junction box, Or perhaps boiler need servicing which is covered by home service companies.
 
If you're competent and happy to work with live 230v, get a multimeter and check whether you're getting anything on your orange wire.
 
Yes I have checked turning just hot water on (with heating off) does work because boiler is working (has a flame icon on display) and gas meter runs.

But heating not come on it's own. Problem because every time I need heating I have to turn water on which means very hot water throughout day bcz we need heating on. It also means boiler working harder so is gas meter.

Normally just had water come on timer at 1 hr in morning and 1 hr in late afternoon and that was sufficient for our household.

I have tried resetting the programmer off few times and boiler few times no avail. Tried settings on the Honeywell programmer with 2 settings one is standard and other mini programmer setting to no avail. I have left it on standard now. Tried default settings on programmer as well.
 

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