Electronics

Thanks for the comments above, Looks to me like I need to fit a fan to pressure the air into the bilge section and then let natural convection lift heat from the top. Noise - Never considered this ! , but now I think, any conduit that conducts air will conduct noise , hence when it comes to the inlet/outlet tube I will have to consider carefully the postion. A fan lowering the noise makes sense, as itl puts pressure on the sound waves leaving the engine trying to travel up the tube. cheers

Neil2 - thanks , air intakes on the side with shutters interesting , but like you said shut when running makes no sense for me , as when running against the tide , the engine will be working much harder than on the canal and my deck will be sealed against the elements salt water etc. So this is just when I need air into the engine room. Aread2 - Yes your prob right although current will be minimal when I do runs across the Humber I run a minimum boat 12V Nav lights and engine ignition only, but your right the alternators are another large heat source. Eeyore - sounds a good design, think I would prefer over side vents , Cereal tiller - Yes I am thinking of one bilge level near engine block/alternators and one at the top- hot air exhaust , just read someone added a 12v fan on the exhaust pipe to add air pressure (but dont want to make complex if I dont have too + another thing to worry about if the fan stops mid Humber)

Yes good point , 50 Hp Shire Barrus, water cooled using side tank keel tank.

Hi everyone, I am fitting a new engine this winter and a new (good fitting) deck above the engine room boat is a semi trad. For the first time ever I have to consider air intakes. The manufactures specification sheet concerning air intake is nothing to do with running of the engine air intake but all about the 'Engine block ambient air temperature'. It states upon my calculations that it requires two 6 inch pipes leading to the engine room from the outside air. That's fine with me I will fit to the spec , but I lack info on the following ;- 1. Do I leave as two pipes or use forced air (i.e small fan , and then push or pull ? ) ? 2. Where do the pipes end in the engine room ? ( hot air rises , so Im thinking above the engine but cold air sinks , floor of the engine room ) 3. How do I terminate at roof level do large domes exist , I have to stop rain etc ? 4. What do I use ? (thinking of using bathroom duct pipe , but will it last ) My boat at times will find itself out on the Humber river so the deck floor will be sealed hence my focus on getting the air intakes right as on river/sea passages. Thanks in advance for any comments and info from those out there who know more than me about air intakes. cheers

Thanks DaveP - So I nearly get, lets say 5.7 KW in full sun.(100,000 lux) Based on my current actual light reading (will be worse in Jan) of 3500 lux I would get around 200 watts which will power my fridge during daylight hours , needing to start the generator to make up for the night short fall. Thinking of heat sinking the fridge to steel of the boat hence (depends on door opening times) I could make the fridge more green ie it only switches on 50% of the time during winter. But lets stop here this is fictional as you need a 70' boat covered in panels and at lets say even with bulk pricing 22 panels at £300 equals over £6,500 not a real solution and someone will point out how many gas bottles you could buy for that amount (if I had a gas powered fridge) Plus DaveP your right who would want to cover their whole boat in panels even if given them for free. In practice I think I will add three panels thus the four panels in series will feed the 48V directly into the Inverter (remember inverters are getting better , but they still take 30-40 watts just to power up) So with my 200W fridge if Im out during the day I have about a 230-240 watt constant boat electrical load so a four panel set-up should provide about 15% of my needs during the winter daylight period.

Measured my old Sanyo 200 watt panel today (200 watts in full sun i.e 100,000 lux light level) Light reading today on the cut was just over 3500 lux (no shade) so maths wise panel should generate 7 watts and the meter says its delivering 6.8W so not bad from an old panel. OK so lets say I generate from 9 this morning until about 6 tonight so I get a total of approx 60 watts. That will power my fridge for about 20 minutes, not a lot !, but on the plus side thats 60 watts still in the battery bank. Thinking about adding another 3 panels next year but from the above at this time of year that still gives only 1hr 20 min of fridge time per day. I might work out tonight that if prices dropped on panels and I covered a bigger boat 70' how much could you generate with dual Amp/Cry panels fitted across the whole roof area.

Personally I hate generators , Petrol - fire risk, storage problem and then theres the noise, you could buy a generator to run off your engine I dont think you will need to run that long to make up the solar short fall ? or think about buying another solar panel and running it in parallel with the panel you have.

Best panels on the market are Panasonic (Sanyo) they are mix of amorphous and crystalline they work better in low light (i.e UK Winters) and give more output then mono or poly based panels, are they worth the extra price , depands the value you put on having more energy from the sun.

Its more expensive at first but running a boat at 230V ac via an inverter can save money in the long run (esp new builds) over the price of all those 12V items. I would fit a 3KW inverter dual feed, shore power and a 3 KW generator from the engine. The next thing is to ensure you buy an A plus,plus rated washing machine.

Like Mike said above, if sunlight you could be down to 25% already on the panels showing 13.2V. Your battery is taking charge (slowly, just ) but is loading the solar panels hence your seeing 12.5V, I would return the controller I dont think you have a fault there , your just short of current and to correct that you need more sunlight. At 12.5 volts that shows the battery is at about 80% capacity (12.75V approx = fully charged)