stegra

Lots of (probably most) houses have the washing machine waste plumbed into the sink waste without a non-return valve. The hose should loop up higher than the sink's water level to prevent the dishwater flowing into the washing machine. I used to have one that didn't and it flooded the kitchen a couple of times when I opened the washer door. The water from the washer might flow into the sink a little, which isn't really a problem apart from when it pushes the plug out and you lose a full sink of hot water.

If the bollard has a 16a trip you won't get much heat, especially if you're likely to use electric kettle, toaster, microwave, vacuum or additional heaters etc at the same time. It also needs to be well insulated underneath which could be tricky on a boat.

Yeah. The NVRs are probably not necessary, as I mentioned. If you use a solar circulation pump to circulate the water, you'll need an NRV in that circuit to prevent the cold water bypassing the tanks when a hot tap is open. A clack valve would offer least resistance.. I've just tried blowing through one of those pumps and there's no resistance at all. I'm not sure why you would only run the pump when the engine or solar is working. I would run the pump whenever I wanted a bath, regardless of the heat source. All other times I would just heat one calorifier. I know pretty much nothing about solar water heating so not sure if it's realistic to fully heat two calorifiers from what will probably be a modest sized collector. From what I've seen in Turkey, Greece etc. they appear to have a large collector angled to the sun for a moderately sized tank... And a warmer climate. Maybe someone with some experience will be along with what's achievable. The only time at looked into solar water heating was when I built my motorhome. The issue then was how to prevent boiling, but that was only going to be a 10 litre tank. If boiling could be a problem, the pump could be thermostatically controlled to circulate at a given temperature.

Pretty engine still seems to be there.

Not sure why you didn't buy a marine exhaust. My Webasto came from the ebay reconditioner (mp & h, I think) who seems to be well respected on here. It included a sikencer like this: https://www.ebay.co.uk/itm/22MM-MARINE-EXHAUST-SILENCER-MUFFLER-STAINLESS-EBERSPACHER-WEBASTO-DIESEL-HEATER/183762469482?hash=item2ac918c26a:g:7AoAAOSwUMxaGHkR Edit: I see you can get pressed ones for £7.29 on ebay so I guess that's why you bought it.

Quite a few assumptions here so this might not be relevant: Assumption 1: You're going to use the bath occasionally rather than daily. Assumption 2: At least one of the calorifiers has two coils and an immersion boss. Assumption 3: You're so rarely on shoreline that an immersion won't be missed. So. I think it would be best to concentrate on heating one calorifier for daily use and only use the second one on bath nights. Swap the immersion for one linked to by Chewbacka above and connect that to your solar collector. If you find yourself on a winter mooring with shoreline, it's not such a big task to swap it back. Use the two coils for engine and Webasto. When it's bath time, circulate the water around the two calorifiers using a pump with non-return valves to prevent pushing the water back to the main tank (probably not an issue) or sucking air from an open tap (again, probably not an issue). The circulation pump might need to be weaker than the main pump to prevent problems (not sure about that). Anyway, here's my expertly rendered diagram of how it might look. Not sure if either, both or none of the NRVs (marked as diodes) are actually needed and if they are, clack valves might be better given the relative weakness of boat pumps. As Onewheeler said, an expansion vessel might be needed: Edit: Needs an NRV in the pumped circuit to prevent the cold water bypassing the calorifiers and flowing through the pump.

I think your circuit is too simple. The engine and solar collector only heat the vertical tank but you are drawing that hot water through the horizontal tank, which will be cold unless you heat it with the Webasto, so the drawn off water will start cold and only get slightly warmer as more is drawn. It would be better if (other than bath-times) you were able to draw the solar or engine-heated hot water from the vertical tank directly. The Webasto-heated tank doesn't care that its water has come through the other tank, so that's not a problem. Maybe you could have some kind of diverter valve at the top of the vertical tank and bypass the horizontal tank on sunny days or after the engine has been run. If the vertical tank is cold, the valve is directed through the horizontal tank and the Webasto is used. I assume from the drawing that on bath nights the Webasto and engine are used.

https://www.ebay.co.uk/itm/4-Piece-Socket-Converter-Adaptor-Reducer-Set-Female-To-Male-1-4-3-8-1-2-Drive/283516550991?hash=item4202e73f4f:g:XMkAAOSwgbRdA8BS You'll have to use the 1/2" to 3/8" and the 3/8" to 1/4" together.

If you mix the water in both calorifiers at all times you will use far more energy than necessary for your normal daily needs. You will have to heat all of the water in both to your desired temperature and lose the advantage of thermal stratification (more relevant in vertical calorifiers) where the water at the top heats up first and can be used for washing dishes or a quick shower without waiting for the full tank to heat. I think I would keep the tanks separate except when water was needed for the bath and find a way circulating the water for that. This of course doesn't account for the solar but I'm sure you can use the same circulation system to transfer the solar heated water to the original tank. A solar circulation pump might be suitable for mixing between the two tanks: https://www.ebay.co.uk/itm/DC-12V-Water-Circulation-Pump-Solar-Water-Pump-Brushless-Motor-3M-8L-H-UK-HOT/174016643721?_trkparms=ispr%3D1&hash=item2884334289:g:lsQAAOSwhvFdbOe9

Yes. And the volume of water makes no difference, only the levels. When you open the top gates on a lock, the additional volume of water from the pound doesn't increase the pressure on the closed gates. Likewise, if you dive down 3 metres in a (saltwater) swimming pool the pressure is the same as if you dive down 3 metres in the middle of the Atlantic.

Or join two different sized open vessels together with a pipe at the bottom of each. If the greater volume of liquid in the larger vessel exerted more pressure it would move along the pipe and increase the level in the smaller vessel. That doesn't happen.

Just found a website that mentions UV vulnerability. The paragraph headed silicone details it: https://www.regencyglass.co.uk/sealed-units/sealant/

That was me who made the suggestion about the UV. On conservatory rooves sealed units are sometimes made as a stepped unit where the top pane overhangs the bottom edge to form the drip. In these cases the spacer bar will be a few inches up from the bottom and not covered by an end closure as it would be with a standard unit or polycarbonate. The suppliers I've used have covered the spacer bar and sealing compound with sign-writer's vinyl to protect from UV. I understand that some high end companies have the glass painted prior to making the units, similar to the black edging around a car windscreen (which may perform the same purpose). The problem is apparently with the sealing compound but it might be that technology has moved on and the UV protection is no longer required.

When the police searched my motorhome at a festival they found a syringe. They also found a packet of Rizlas with the corners torn off. I'm not sure what they thought when I showed them that the syringe was for something going by the name of Crack Cure.

Stick your battens with a PU adhesive such as Sikaflex. Space them to suit the boards, probably 600mm or 400mm centres. You can put your conduit in first if you're sure where it should be. Otherwise, you can easily cut a groove in the foam later; PU foam doesn't rot cable insulation like polystyrene does. There's another thread on insulation that's just been reignited today:

When I've used it in buildings I've stapled it to the rafters then nailed a batten onto it so that I could screw the plasterboard on. You would lose quite a bit of space on a boat doing that though. Sometimes the screws will go through if you apply a lot of pressure to compress the quilt but it only takes one to snag and you have to take it all back off. Normally a lot more than one snag.