Very little hot water

Hi,

I am new to this forum and this is my first post so hopefully someone can help.

I originally had a Boilermate 2000 which was installed by Miller Homes when the house was built in 2004. I had nothing but problems with this (it actually caught fire twice) so I replaced it 3 weeks ago with the Boilermate BP. The tank is 125 litres. I have left the HW setting on and have the central heating set to 'Twice' There are no issues with the heating however when I try to run a bath I barely get to fill a third of the bath without the water running cold. If I leave this for half an hour or so there is more hot water. We cannot even have 4 showers one after the other as the water would run cold. I know the tank is not that big but if the water wasn't being used before hand I should surely be able to run more than one third of a standard sized bath without it running cold? Any help would be greatly appreciated. Cheers!

125 litres is the smallest one.
One bathroom / 2 people is the max.
Have you checked that the store stat is set correctly?
Mike
MGC/H2O
Norfolk

Thanks for the swift reply Mike. I am not sure how to check the store stat. Do I take off the front cover of the Boilermate to locate this? Also, if I run the water at a reduced flow I seem to get more so not sure if that may help with the diagnosis of the problem? Sorry, I am a total novice when it comes to things like this so your help is much appreciated. I wouldn't have thought there should be any major problem as the unit was just fitted as new around 3 weeks ago. I am loathe to call British Gas as they visited me 15 times in 2011 trying to 'fix' my original Boilermate.

Thanks again!

Commission the unit as per the book.