T&T: sea water alarm

[Robin]

I have never heard of a non invasive water flow alarm ....meaning one that
works without cutting into a water line.
The Aqualarm in fact must be inserted into a section of cooling hose..it has a
flapper valve inside which water flow opens...I've used a pair on my boat for
about five years and like them...they sound a brief alarm at engine start
which serves as a test signal, then shut off as salt water flows...

An alternative might be a temperature sensor clamped onto a section of an
engine, or a section of coolant pipe, which alarms perhaps 20 degrees above
normal temp. A temperature sensor on raw water pipe would likely register
nothing if water flow was lost ...until too late...

Rob Brueckner
Hatteras YF