Posted: Sun Nov 28, 2010 9:27pm

Dear Sirs, I have recently bought a 43 foot steel hulled motor cruiser that I intend cruising the inland waterways on and to live aboard. At present she has a small (approx 5-10 litre) calorifier and a 4.0 kva generator, no gas. I am looking to upgrade the hot water system and cooking facilities but don't know what size calorifier would be appropriate for two (occacassionaly four) people. I don't want to be dependent on shore mains although I will probably winter aboard in a UK marina. Please can you advise as to what would be the best way forward. Thankyou.

Posted: Mon Nov 29, 2010 8:57am

Dear Jill, I would be interested in what heating system you have if you intend to winter aboard in the UK. The reason I say this is because if it is any form of wet (radiator)central heating then it may also be able to heat the calorifier. If it is at all possible I would want to heat the calorifier from the main engine, the generator and also any wet central heating system. This will make maximum use of waste engine heat. IT implies a three coil calorifier or a two coil one if the heating is by hot air. Calorifiers store the hot water for use later so the smaller they are the less hot water you can store and , more to the point, the faster the temperature will drop as you add cold water to make up for the hot water you have drawn off. For this reason I always recommend the largest calorifier you can reasonably accommodate and what that size is depends upon you boat and/or where you can move the calorifier to so a larger one will fit. If you plan to winter in a marina you may want to consider ensuring the new calorifier has an immersion heater fitted (max. 1kW) so you do not have to run the engine to get hot water when in a marina. Tony Brooks