Both lights on (red & green) .. but no hot water

Howdy folks (Im a newbie to the site .. but from scouring the forum, it looks darned decent and Im hoping you guys can at least narrow down my problem so that when I can find an engineer who will come out to North Wales and to whom I can at least suggest what may be causing the problem).

So .. what is the problem ?? .. well over the last week or so the amount of hot water I have been able to get from the taps before it just runs cold has reduced ... until this morning when I got 30 secs of warm water in the shower .. and from thereon in, nothing hot, not warm .... its just freeeeezing !!

I have economy-7 heating with the day-time (off-peak) switch always set - so there ought to be hot water at any time, I would have thought. This place is empty in the day-time, so I know no water gets used from when I go out to work, until I come home .. I've also flicked the on-peak switch to see if that has any effect ...

I can hear a "whoosh" sounds for a few mins when on-peak is switched .. and I thought wahey ... it looks like its heating the water.

The pulsacoil unit itself it warm / hot .. and I've checked the header tank .. all levels are fine (even though the water is a mucky shade of brown!)

After leaving it on "on-peak" for a couple of hours I have just checked it now ... I still have no hot water (grumble, grumble!)

I have taken off the big front panel .. to see if there is any reset button or something .. but there isnt .. just lots of wires which I wont even dare to touch or go near).

However .. there is another red led which I cannot ordinarily see as it is behind the metal casing. This red led is flashing twice a second ... whether this means anything to you experts I have no idea !?

Could anyone offer a suggestion on what may be the problem, and also offer some contact details of an engineer they would recommend who lives close-ish to North Wales?

Thanks, in anticipation of someone replying!

Ian

Doh !! ... sorry ... I mis-informed you .. only the green light is on .. not both lights as I had previously stated.
The red light on the display panel is not lit (I was getting ahead of myself there).

sorry for the confusion, I'm obviously tired and overworked!

Hi,

If all taps are running fine and it is the shower that is giving you problems, I would fist recommend you replace the shower cartridge as this has been known to cause similar problems.