It is now common practice to install (or even relocate) a combi boiler within the loft space of homes. The advantages include no space within the normal living areas is taken up (by the boiler), any noise from the boiler (to the living areas) is reduced and the boiler can be located close to the bathroom, giving near instantaneous hot water to the taps.
But a colleague’s combi boiler (installed in the loft) recently suffered a failure of the heat exchanger, resulting in a leak from the boiler. Had the leak been within the central heating circuit, the resultant loss of pressure would have shutdown the boiler – and the amount of water leaked minimal. As bad luck would have it, the leak was in the DHW supply side of the heat exchanger, so the first my colleague knew of the problem was on returning home to find water dripping through the upstairs ceiling.
Given that the heat exchanger of any combi boiler will fail eventually, should you have a combi boiler installed in your loft space – I would recommend you purchase a Water Leak Alarm (from your local £ shop) and position it beneath the boiler.
The device (Water Leak Alarm) looks much like a smoke alarm (in size, shape and colour), but is placed on a flat surface rather than on the ceiling. For your £, a PP3 battery is not included in the price.
I have lived at my current address for 10 years – there was a combi boiler installed in the property when I moved in. In that time, I have had two boiler heat exchangers fail (leak). I am not going to mention the Brand, but I doubt it to be significantly better or worse than others. If my boiler was in the loft, I could well have suffered significant water damage as a result.
The alarm has small metal pins protruding from its rear – once the pins are electrically connected (even through the relatively high resistance of the water bridging them), the alarm sounds. The alarm can be tested by bridging the pins with your fingers.
The alarm is not as loud as a smoke alarm – but should be loud enough to be heard from the loft, or similar location.