Filling Bath - Leak

Hi,
Whilst filling our bath upstairs, we have a leak that ends up spouting out of our fire alarm downstairs that is linked up to our main electric circuit board (which is directly underneath our Boilermate II) - we think it's coming from the hot water feed pipe, as this is the only thing that's on when the bath is filling? Is there anything that we need to ask specifically from a specialist plumber? So many in our area don't even seem to have even heard of Boilermates! We think that we can claim the work back from the people that built the house as it's only 7 years old? Any help you could give would be much appreciated.

If the pipes were leaking, they'd leak whether the bath was being filled or not as they're always full of water. Sounds more like the bath waste is leaking round the plughole. That or the bath's cracked. Pull off the side panel and take a look. You might save yourself the cost of a plumber.

Oh and I'd ask the people who built the house why the hell they put the main circuit board directly under 120+ litres of water.

Thanks for the quick reply. It is baffling everyone that we speak to, as someone else mentioned that the pipes are always full. We have already pulled the bath panel off - there doesn't seem to be anything damp under there at all? We have also filled the bath up with water from buckets and the leak hasn't started up. We have also tried just filling the bath up with the cold tap and no leak. It just seems to happen when the hot tap fills the bath...which is obviously what you need
Maybe it is the plughole leak?