Combi Boiler issue or power shower issue

[Sully2014]

Good Morning All,

I have an ariston combi boiler - for back ground info the boiler is about 2 meters from the gas mains and it is supplied using a 15mm pipe. it heats a one bedroom flat with 6 radiators ( one hasn't worked for a while)

The boiler model is Cas he 30

The boiler is always turned upto the max on both HW and Central heating.

The hot water can be a bit intermittent but recently the power shower which is a MIRA 915a seems to have a problem getting hot - the hotwater pipe leading to the shower does seem to be get hot so im wondering if this particular issue might be an issue with the temperature regulator on the shower? I did come across a mira spares page and wondered if this could be the issue - has the shower scaled up??

http://www.showerspares.com/mira_shower_spares/mira_all/mira_915_915/

I wondered if anyone experienced can confirm why the boiler is always on full capacity? this is something I have always found strange?

I have never serviced my boiler ( 7 years old I think) and although the issue of having the heating on full power has always been the case - I wonder would a service help??

Thanks for your advise on both these issues?

 

[muggles]

If your hot water is ok at other outlets then the issue is most likely to be with the shower valve

 

[ChrisR]

The pipe will only get hot if there is water flowing through it to the shower. It can't go so far then stop.

Check your kitchen tap, is the HW ok at constant very low as well as high flow rates.
If not, or the waters goes hot and cold, the boiler needs repairing - scaled up.
If it's fine then it's probably the mixer.
Try the shower at low flow rates.

7 years - boiler probably needs several things doing, beyond a simple service.