As the current owner of Aquarius, thanks for all the comments.
The engine (Beta BV1505) is direct water cooled with it´s own skin tank. As is the genset. The engine for the the genset is a Beta BV1305 which uses between .75ltr/hr to 1ltr/hr depending on load.
The solar panel is a 250W Sanyo HIT the most efficient panel (19%) I am aware of. MPPT is a Steca.
There is also a secondary cooling system for the engine which has an intake from the weed hatch if temp reaches above 85deg C. There is a heat exchanger between the engine and skin tank, the cold water from the river/canal is expelled on the the port side. If wanted this system could be disconnected in ten seconds but is useful on long river runs. The previous owner spent time on the tidal Thames and Trent.
The calorifier is heated by the engine, the heater element is 1kw. A brand new Surecal was fitted by Hilperton in 2010. The calorifier has insulation already fitted. The immersion element is vertical. In October last year I had to leave the boat for two months to go to India for work. Being paranoid about frost damage I put a spare single duvet on the top of the calorifier to prevent any frost damage.
The calorifier will produce hot water after 30 minutes, after a long run you will have hot water for a couple of dayse genie.
Powering the immersion by the generator is also an option. Given the power output of the gennie whenever the washing machine was used I would always put he immersion on at the same time as well as charging anything that needed charging charging to put some load on the genset.
When I first got the boat it had 1" galvanised steel pipe running off a backboiler on a Parkray stove running the length of the boat. I replaced the stove and replaced the galvanised steel with 28mm copper (gravity/convection) intending to add rads but found it worked so well without any rads that I left it with just the copper pipe. It is an unpressurised system, completely safe and has worked perfectly since 2009.
Boat was repainted in 2012, absolutely no rust on superstructure. Water tank cleaned at same time and new cratch cover fitted.
Water in the engine bilge was due to a new bilge pump fitted by me with with an off/off/auto switch being left in off position by mistake.I thought I had mopped most of it up, apologies if there is anything left.
Please contact Paul at Braunston with any other questions and I will do my best to answer any queries to the best of my ability.
Surveyor for the hull was Craig Allen, who I had never met before but found very straightforward to deal with I have no problem with any potential buyer contacting Craig direct.
Sorry for the decor!
Cheers
John