Is it safe to run the calorifier on empty?
I have a 50ft boat fitted with a twin-coil calorifier. I drained the water tank and system to minimise the risk of ice damage over the winter. Given that the calorifier is empty, will I do any damage to it or the hot water system if I run the engine for a long period?
QAIn most cases, no damage will result from running the engine with no water in the calorifier. However, the water normally tends to dampen vibrations in the coils so (in theory) a coil might workharden and snap. Such vibration could do the same to the calorifier skin if it’s made of thin metal.
On the odd occasion a calorifier failed when I worked on the hire fleet, it always seemed to be a horizontal one and often at the spring recommissioning, so I would be more wary about doing it with a horizontal calorifier. I have run my own engine for long periods without water in a vertical calorifier without suffering any damage.