Big COL

John I met a family on a gas free boat last summer and they were selling it. the main reason was the range that was in the boat for cooking was oil fired, and by the time it reached a sensible temperature to use they were nearly naked. His opinion was great in winter, but was fed up living off sandwiches in the summer. I would think there must be some insulated ranges to eliminate this problem as there are plenty of people who want gas free boats

Chris Victron have an inverter that tops up the shore supply, this would lighten the drain on the battery bank.

Paul If you still have no heat in the rads then there is something else on the system causing a problem, either there is air trapped somewhere, or there is a problem with the pipe work where you bypassed the gas boiler, because as you describe the system set up it should work. Its difficult to work out whats going on not having seen the pipe work so can we establish some basic facts and then go on from there 1 With the pump running and the stove running are you getting hot water on the return to the stove. ie the pipe that comes into the bottom of the stoves boiler. 2 If there is no hot water on the return how far is the hot water getting on the flow ie the top pipe out of the boiler. Forget about the pump pumping air, this is a flooded system if there where any places that air could get in then it will leak water when the pump is not running. The pump is only there to move the water round a loop, air in the system is the most common cause, it gets trapped in places you would least expect I have had enough experience with this problem so know the problems well enough. Don't get disheartened you will get through this.

Timbo 1 Why would the highest pressure be at the lowest point? 2 What positive resistance does a boiler cause bearing in mind that on most systems on boats the pump is overrated for the boiler performance and usually need slowing down. 3 On a closed system that has had the air evacuated from it how does the pump suck air in any opening in the system will leak water?.

John On a pumped system natural convection does not apply, as you normally come out of the boiler and drop to low level behind the boiler and then run flow and return at low level, the rads and cal are just tappings off a large loop of 22 MM pipe. the pump can go anywhere in that loop as long as it is configured to keep the water moving in the correct direction. The only downside to pumping the flow is that the pump has to handle the hottest water on the system, the advantage of having the pump on the return after all the rads is the water has cooled a little. If you were converting a gravity system where the flow is running at high level then yes you are then right about natural convection and the pump needs to be at low level on the return.

Paul If the pipe in your picture from the boiler is from the top connection on the stoves boiler then this looks ok, the inlet to the pump is under the motor and is connected to the flow from the stoves boiler, and the outlet from the pump which is at right angles to the motor is connected to the rads. In this configuration you are pumping the flow (just for information) this should work once you have all the air out of the system. My only comment on this configuration is that the pump is having to handle the hottest water in the system, but it will still work ok.

Paul Fingers crossed

Paul Have some more info. On a bolin pump the water inlet is directly under the motor, and the outlet is at right angles to the motor, the polarity is as you would expect, red- positive, blue-negative. Sorry I had to leave you at lunch time, had an emergency at work.

Paul/John The pumps are directional there is usually an arrow on the outlet showing the direction of flow. polarity needs also to be correct as Dor said it will still run, but not work very well

Paul is the pump going in the correct direction the circuit should be out of the top of the stoves boiler through the rads through the pump back to the bottom connection on the stoves boiler the pump should keep the water running in this direction. so the flow from the stove is the inlet to the pump and the outlet from the pump is the return to the stove

Paul you can run the heating on the aldi but not with the stove lit? if you are using the stove and the pump is part of the aldi bypass the pump must run the in the correct direction or you will be pumping against the stoves boiler flow

Paul You will not be able to run both stove and boiler together as you will have opposing flows, the boiler will be able to work on its own with the stove not lit, if you want to use the stove I suggest you fit a by pass pipe infront of the boiler. this was covered in a post in the last month. If you are only using the stove for space heating then by pass the stove ie link flow and return, drain the stove and leave the stoves boiler connections open

Paul Not enough info 1 Is the pump on the flow/return? 2 Are you running stove and boiler

Do you not think that we are all a little guilty here? The thread was started with a simple question and was dealt with quite quickly, it was then expanded upon by us guys who have enjoyed the banter that then ensued. I wonder if this may be detrimental to the forum in as much that the level that some of the threads are taken to, is off putting to readers who are reading the forum looking for basic information and so may deter them from posting a basic question. The contributers to this forum have a wealth of information collectively and I assume get a great deal of enjoyment from their involvement, but as John quite rightly stated we tend to digress and take it to another level. Perhaps there is a call for a techy section where threads can be moved to when this occurs. I am not being condescending here but from experience when subject matter starts to go over my head I tend to shut off, there will be a lot of readers that do not understand the technical replies and will probably do the same .You could argue that there is the information within the replies to help these sort of readers. It is there, but when a group are debating a subject and have differing opinions it's difficult to discern the correct pieces of information, its not like following a set of instructions or learning it from a book. These are just my observations and thoughts I am well aware of principal of forums but it just seems to me that KISS should apply to the general sections and have a techy section for the hot debates. It will be interesting to see if anyone has similar thoughts

Paul I know exactly what you are mean here. My marina supplied me with an inline meter with a plug wired on at both ends, the chap got most upset when I informed him where he could plug it in. He was most insistant that this was how they came wired, and only after a demonstration of pluging it in with a test lamp on the other end did the penny drop. It turned out that the meter had been used before,and was handed back when the boat left, the owner of the boat had changed the socket for a plug so it matched the configuration on his boat. Enough said.

Does this make it environmentally friendly?

Dor It would be worth trying electro plating then.

John Found your improvements very interesting, as this is a subject that I have very little knowledge of, the extent of my knowledge ends after the boat is trimmed. Any thoughts on what I term as boil over, when making a turn with quite a few revs on a quantity of water passes over the top of the rudder, this seems to me to be a waste of energy. I have seen rudders on boats that have a piece of metal welded to the top of the rudder to form a T shape, this looks as it would stop this boil over, in discussion with a number of hull builders none of them seemed to think that the boil over was a problem, and therefore no need to add a plate on top of the rudder. I also have a small problem with my current boat in that when requiring to stop quickly, once in reverse and the revs go on the stern lifts, air can be heard rushing in under the counter, and on she sails with very little breaking effect. It's not over propped, in fact its slightly smaller than recommended, the trim is correct about 2'' of water over the counter. Would appreciate some views on this.

At long last have we put this thread to bed? NOW! about rubber hulls.

Richard In a single cell the construction is of two separate plates sitting in electrolyte, the positive plate is the anode and the negative plate is the cathode, the resulting chemical reaction produces a voltage of 2 volts approx across the plates. The anode plate is the one that suffers the deterioration. Substitute this into the theory that the same reaction is happening with the boats. IE your boat is the positive plate (anode) another boat is the negative plate (cathode) canal water is the electrolyte, a single cell exists, and your boat corrodes. This is as I understand the theory that is being put forward, I like John am not convinced that this is so. Rubber hulled narrowboats is the answer.

Chris Reverse the polarity.

Surely if the anode and cathode are shorted together as I was trying to say in the previous post, then no reaction can occur. A cell works from the reaction between an anode and cathode separated from each other sitting in the electrolyte. This is why batteries cease to work, the separator between the plates after a period of time breaks down. The plates (anode and cathode) short together and the cell stops working. This is what I was trying to describe in the previous post (not very well) but if one boat is the anode and the other the cathode and they are hard wire bonded how can any reaction take place, to add to this debate in a cell it's only the anode that suffers the corrosion, which follows in the case of the two boats only one would suffer.

Maffi I agree, but it will still be there for the future.