GMS General Marine Services sells, installs and services a range of marine calorifiers manufactured by Gianneschi. They are simple to install and provide domestic hot water for all sizes of craft.

The units are fitted with an integral coil (or coils) which, when connected to the engine jacket water, transfers heat into the calorifier. This utilises engine heat that is otherwise wasted, resulting in a very economical hot water service. The amount of hot water generated is linked to engine running times and usage, but as a rule of thumb the calorifier will remain hot whilst the engine is running. The units are insulated to ensure that the water stays hot for periods when the engine is not running. Generally, ample hot water supply is available on demand.

Gianneschi can add a pre-plumbed kit to their range of cased marine water heaters. The kit consists of a blending valve, a pressure relief valve and interconnecting pipework. This facilitates the installation of the water heater making it more installer friendly. This kit can be supplied fitted to all models on request.