Onewheeler

Bow line round a bollard, ditto stern line, stand in the middle holding both. Avoid lunchtime when the lockie is on lunch break.Or, going up, tie one end on and control the other.

On the Warwickshire Avon the locks do not behave nicely. I find it easier going up to tie the stern to a bollard and take a long line with you to the top gates. Operate the paddles a little at a time until you get a feel for what the boat is doing.

All good points. However wash from the big boats is not really a problem when moving and they are mostly considerate. Mostly. Drag when moored is more of an issue. There have also been a lot of closures in recent years due to lack of water on the smaller and sometimes bigger canals. Another thing to consider is how to operate locks. Are you single handing? Some of the locks are deep and need lines moved as you go up. You'll need to work out a procedure for going up and down. The usual method is to take a line from the front to a bollard and keep tension on it with the engine. Harder without a crew to control the rope.

The downside is that you'll usually pay an arm and a leg for water and electricity in Belgium. Typically 1€ per kWh or 100 L. It's usually included in the fees in France. Remember that Belgium operates as two countries: the licence in Flanders is fairly cheap, and free in Wallonia. I've not been, but I think it's even more complicated in the Netherlands. Also, often the electricity supply is centre-tapped in Belgium which is confusing. One should not rely on neutral being on the "proper" pole of the connector. It's useful to have a phase-reversing adaptor (a pair of connectors cross-connected) and a socket tester - like https://www.screwfix.com/p/lap-ms6860d-socket-tester/91596

I think adaptors are available, but easier to buy a new regulator.

If you've got a holding tank, you'll need to be able to pump out yourself. Ideally connect it permanently so you don't have to dump it all in one place! The DBA is worth the fee just to access the online waterways guides. They are updated by members and are generally a comprehensive and accurate list of where it is feasible to moor, as well as facilities and costs. Another thing: in France diesel is not seen much in marinas and is usually expensive. Most boats carry cans to fill up at service stations. VHF is useful on the bigger waterways, and essential if you are going into Belgium. There are specific regulations, and you can expect to be inspected occasionally. Fire extinguishers and lifejackets must be in date. You need a bucket on a rope for fires! Look at the DBA knowledge guides (but remember that a lot of the more complicated stuff relates to boats over 20m). I'm not sure if nav lights are compulsory or not (if not traveling at night).

Hose connectors are nearly all bog standard BSP. Shore line connectors are nearly all the usual 16A type. It is very useful to have a couple of 30m mooring lines and some very big mooring pins. Main difference is that nearly all toilet waste goes over the side. I've only seen one pumpout in France. Elsan disposal can be found at municipal camper van sites which are often waterside. On many waterways the only feasible mooring is at dedicated spaces. Mooring online in the middle of nowhere can be impossible due to depth, rocky banks or wash from commercials. A narrowboat is not ideal. Many moorings are on pontoons and limited to 15 m or less. It can be done though. More specific advice on the DBA website but you need to join to access their very useful waterways guides and forum. Martin/

Possibly a 610mm shower tray which is the current standard size. Google will find lots. Something may suit.

Ours decided to separate into two halves recently. Held together with a bayonet fitting but without the clicky bit at the end. It dumped 250 L into the bilge.

That's a pity, the C&L weren't bad for the price. I've just fitted a couple in my house. We were lucky to have bought just in time. It's worth adding some PVA to the joints to make them sturdier.

It might be feasible if installed as an adjunct to a stove, and would make the boat feel very comfortable. Easier to fit on a new build. Maybe just fit it up the middle 1 m of the boat (assuming a narrowboat) as the edges are usually furniture. The ballast goes up the edges. Build a Celotex wall to separate the centre section from the ballast area, and line the baseplate with Celotex. Typcial heating mat is 150 - 200 W/m^2. 50 mm Celotex has an R-value of 2.25 m^2 K / W so a deltaT of say 40 K water to heat mat would only lose about 17 W/m^2 to the water, anything left would warm your feet. 10 m^2 of 150 W/m^2 would therefore put over 1300 W into the boat. Not enough to keep it fully heated but it would certainly make the boat feel more comfortable. Domestic underfloor relies on a low heat input over a large area. A narrowboat is only the area of a small room in a house.

I'd try to keep it simple. Tank H has webasto and engine Tank V has solar (with its own pump and controller) and spare coil. Fit the Webasto outlet with a three way valve (including midway option) to feed H, V spare coil or both. Cold feed to V comes from hot outlet of H. DHW feed comes from V. Normal operation has Webasto going to V or use solar in V. Bathnight has Webasto powering H (and V if solar hasn't done much). It sounds as if you don't use the engine much, but otherwise you could arrange a small recirculation pump from hot side of V to cold side of H (with a NRV in the cold feed to H and an expansion tank) to get hot water to V. I don't know if you can get three-way valves for 12 V with a midway option, but otherwise take the actuator off and operate it manually (Womanually? Gender-non-specificually?) Some clever Arduino programming with sensors could help, or get very confusing! Martin/

"Hardly no cavitation"?🤔

Might work if you've got enough space under the floor. However (without doing any sums) you would need a thick insulation layer as the area used over the baseplate would be large. Otherwise you'll be circulating heat from one side to t'other. Molten salt storage? 🙄

If you've got that much electrical power then no problem! You'll have a large bath tank as a thermal store! Water has the highest thermal capacity of anything readily available, although it would be interesting to do a conceptual design using parafin wax as a thermal store using its latent heat of fusion.