Hot water problems

[Chad123]

Hi can anyone help?
I live in a flat which has central heating and hot water fed via one main boiler for the block. Lived here 2 years now and the water is always really hot and we could have several showers out of our tank or hat water.
For the past month now we can have 1 hot shower and the water goes cold withing a few minutes. The radiators are still really hot so i know the problem isn't with the boiler.
We have a stat on the hot water pipe that feeds into the hot water cylinder, could this be the problem?
The pipe with the stat on it is roasting hot. There are 3 pipes located next to stat, i may be wrong but this is what i think they do... one is feed in from rising hot water main, this goes into stat, then straight out other side is a by pass to the return to the boiler if the stat is off, the third is below the stat which feeds into bottom of hot water cylinder (this pipe is cold).
Am i making any sence.
Is this the stat faulty or am i completly talking b*ll****s. (probably)
Can anyone help? Don't say call a plumber!!! Thanks

 

[Softus]

Please don't post what you think the pipes do - either become 100% certain or post a photo.

Could you also give the make and model of your boiler, and state how many motorised valves you have.

 

[Chad123]

don't worry i've got it sorted, I think i said everything, there are no motorised valves. As stated there is only one valve which is not electric as all hot water is supplied via an external boiler to the property. There is no boiler in our flat. The make of the thermostatic valve is Drayton which is a 3 port valve.
How can i be 100% certain what the pipes do? If i knew that i wouldn't be asking what the problem was, would i?

 

[Softus]

How can i be 100% certain what the pipes do?

I don't know. All I know about your system is what you've typed.

If i knew that i wouldn't be asking what the problem was, would i?

Is getting arsy your favourite way of seeking help from more experienced people?