DeanS Posted December 28, 2010 Report Share Posted December 28, 2010 (edited) After reading this thread, I went to B&Q today and bought some square 70x70 drainage square tubing/trunking and enough elbows etc to route it from above the stove, down to floor level, and along the entire length of the boat. It looks quite neat, and acts as an edging to the new floorboards I put in earlier...I was wondering how I was going to neaten that up. I've built a hood/canapy out of wood, around the top of the stove flue (at ceiling level), and plan to put the fan in a small wooden box inside the canopy. The air at that point is hot even having just started up the fire. The plan tomorrow is to find a 12V fan, install it, and create slots/exit holes at different points down the length of the trunking. Once done, I'm going to light it up, and put my hand in front of the furthest exit hole, and report back to you lot on how well it works ))) Here are the fan specs at Maplin. Which should I use for best results? Type: 80mm Operating voltage: 10.2V to 13.8V Rated voltage: 12V Current: 180mA Noise level: 31dBA Max airflow: 900 litres/min Continuous life: 60000 hrs 25 C Operating temperature: -10 C to +70 C Insulation resistance: 10MΩ 500Vdc DC dielectric strength: 5mA 500Vac Weight: 140g Overall size: 80 x 80 x 25.5mm Fixing centres: 71.5 x 71.5 x 4.5mm dia Specifications: Type: 92mm Operating voltage: 10.2V to 13.8V Rated voltage: 12V Current: 300mA Noise level: 35dBA Max airflow 1200 litres/min Contiuous life: 60000 hrs @ 25 C Operating temperature: -10 C to +70 C Insulation resistance: DC 10MΩ @ 500Vdc DC dielectric strength: 5mA @ 500Vac Weight: 150g Overall size: 92 x 92 x 25.5mm Type: 120mm Operating voltage: 10.2V to 13.8V Rated voltage: 12V Current: 380mA Noise level: 42dBA Max airflow 2200 litres/min Contiuous life: 60000 hrs @ 25 C Operating temperature: -10 C to +70 C Insulation resistance: 10MΩ @ 500V DC dielectric strength: 5mA @ 500Vac Weight: 200g Overall size: 119.5 x 119.5 x 25.5mm Fixings centres: 104.8 x 104.8 xdia 4.5mm Edited December 28, 2010 by DeanS Link to comment Share on other sites More sharing options...
Pretty Funked Up Posted December 28, 2010 Report Share Posted December 28, 2010 (edited) Out of curiosity, how much current does the circulation pump use, and is it running continuously? Pricey bolin pump but it uses about the same as 1 fan... 0.15a Here are the fan specs at Maplin. Which should I use for best results? Type: 80mm Noise level: 31dBA Type: 92mm Noise level: 35dBA Max airflow 1200 litres/min Type: 120mm Noise level: 42dBA Max airflow 2200 litres/min I used 120mm, 1200rpm, 17.5dBA and 1087 ltrs/min (these figures totally depend on what voltage you feed it, theres no need to regulate it so it varies ) Edited December 28, 2010 by Pretty Funked Up Link to comment Share on other sites More sharing options...
MtB Posted December 28, 2010 Report Share Posted December 28, 2010 After reading this thread, I went to B&Q today and bought some square 70x70 drainage square tubing/trunking and enough elbows etc to route it from above the stove, down to floor level, and along the entire length of the boat. It looks quite neat, and acts as an edging to the new floorboards I put in earlier...I was wondering how I was going to neaten that up. I've built a hood/canapy out of wood, around the top of the stove flue (at ceiling level), and plan to put the fan in a small wooden box inside the canopy. The air at that point is hot even having just started up the fire. The plan tomorrow is to find a 12V fan, install it, and create slots/exit holes at different points down the length of the trunking. Once done, I'm going to light it up, and put my hand in front of the furthest exit hole, and report back to you lot on how well it works ))) Excellent stuff Dean, I look forward to reading your results here! I'll predict that putting your hand in front of the new air vents will disappoint you. The air temp being blown out will feel cold as the air is likely to be at a lower temp than body heat. Even so, air at as low a temp as 20 or 25 degrees C being discharged at floor level will be a Good Thing and WAY warmer than the air currently there (as Quebec has recorded at a few degrees above freezing). This is bound to improve comfort levels. Better to use a thermometer to measure the air temp output because this will give you a true indication of what's actually going on. Mike Link to comment Share on other sites More sharing options...
DeanS Posted December 28, 2010 Report Share Posted December 28, 2010 Excellent stuff Dean, I look forward to reading your results here! I'll predict that putting your hand in front of the new air vents will disappoint you. The air temp being blown out will feel cold as the air is likely to be at a lower temp than body heat. Even so, air at as low a temp as 20 or 25 degrees C being discharged at floor level will be a Good Thing and WAY warmer than the air currently there (as Quebec has recorded at a few degrees above freezing). This is bound to improve comfort levels. Better to use a thermometer to measure the air temp output because this will give you a true indication of what's actually going on. Mike What is the difference between a rectal thermometer, and an oral thermometer. The taste Link to comment Share on other sites More sharing options...
Pretty Funked Up Posted December 28, 2010 Report Share Posted December 28, 2010 The air temp being blown out will feel cold as the air is likely to be at a lower temp than body heat ... Better to use a thermometer to measure the air temp output because this will give you a true indication of what's actually going on. Mike very true What is the difference between a rectal thermometer, and an oral thermometer. The taste very good Link to comment Share on other sites More sharing options...
Robin2 Posted December 29, 2010 Author Report Share Posted December 29, 2010 Excellent stuff Dean, I look forward to reading your results here! I'll predict that putting your hand in front of the new air vents will disappoint you. The air temp being blown out will feel cold as the air is likely to be at a lower temp than body heat. Even so, air at as low a temp as 20 or 25 degrees C being discharged at floor level will be a Good Thing and WAY warmer than the air currently there (as Quebec has recorded at a few degrees above freezing). This is bound to improve comfort levels. Better to use a thermometer to measure the air temp output because this will give you a true indication of what's actually going on. Mike I have a cheap multimeter that came with a thermocouple on the end of a wire. Its great for this sort of thing as it reacts to temperature changes in a few seconds. I can also measure high and low temperatures so I can stick the end in the oven or the freezer. Link to comment Share on other sites More sharing options...
AlanH Posted December 29, 2010 Report Share Posted December 29, 2010 We don't lke warm bedrooms. Ours is warm enough with the stove going in the saloon. Even in the coldest weather we have one window open in the bedroom. Link to comment Share on other sites More sharing options...
DeanS Posted December 29, 2010 Report Share Posted December 29, 2010 (edited) Right. I have results Today I bought a 12V fan. I've connected it, mounted it in a maplin box which has a 70x70cutout in it to fit the 70x70 plumping square trunking which runs from above the stove, down to floor, round back of stove, along length of boat. I then made some 12mm holes in the trunking, as it passes the galley, and as it passes the bedroom, with the option to extend further along the passage. I've taped some tissue paper to the furthest point...and started the fan. The tissue paper flaps merrily...proving hot air above the fire is reaching the far end of the "circuit". When I started, the entire boat was 10degrees. That was 2 hours ago. I started up a roaring fire... Measurement showed over 40degrees above stove (the cheap ASDA thermometer I got only goes up to 40deg Celsius) Measurement at floor level showed 14. Further along the boat showed 12deg at shoulder height. End of boat showed 11deg. I've now had the fire on for a bit, with the fan running. Midway and further is showing 20degrees at waist/shouder height. I'm sitting with a T-shirt on, and theirs definately a difference. I wouldnt say it's spectacular, but considering I had an elec heater 2 nights ago which chewed up about £5 of the elec token...I'm happy. I was going to also buy a back boiler which was going to cost £250...which I may not need. I also used the gas lighter and clicked it at different points to test if the air in the boat was moving at all. It showed that at a low level air was moving towards the stove area, and at head level it was moving away from stove area. I believe the fact I'm blowing air out further down the boat is forcing air to move around more..... which is causing an improvement in the hot air above, cold air below scenario mentioned. I just put the thermometer on floor level near the stove and it shows 25degrees. What's more, sitting further down the boat, in a T shirt...I can feel when the temp starts falling..and when I look down to the stove I can see the coals are dying..so pop in another log etc and things improve again. One warning. The back of the stove gets really hot. You need to put in a heat shield in front of the trunking...I'm going to fit a piece of copper plate or something to match what's on the wall. Overall I think it's been a success but if you do have a lot of money you might want to put in a pro solution. This one was great for me as I'm having to spread my cashflow a bit oh...I've also just realised I had a small top window slat open. silly me... So I guess you can raise all the test results by a degree ) The fan I got is quite loud...but the kids should drown it out. edited to say....measured temp outside the boat = 7degrees celsius. Edited December 29, 2010 by DeanS 1 Link to comment Share on other sites More sharing options...
nb Innisfree Posted December 29, 2010 Report Share Posted December 29, 2010 IME when using a fan to circulate warm air the draught created makes me feel colder. Link to comment Share on other sites More sharing options...
DeanS Posted December 29, 2010 Report Share Posted December 29, 2010 IME when using a fan to circulate warm air the draught created makes me feel colder. The fan is mounted above the stove..near the roof..sucking hot air in. The outlet is further down the boat, through holes in the trunking. You cant physically feel the air moving (as you do with a normal blow fan). Link to comment Share on other sites More sharing options...
Phil Ambrose Posted December 29, 2010 Report Share Posted December 29, 2010 Where does one get the fan you mentioned? Are they cheaper than computer fans? How much power do they use? Check out Maplin's brushless 12v fans, I have been using them for yeqars noe to circulate airr for heating or ventilating. Phil Link to comment Share on other sites More sharing options...
Mac of Cygnet Posted December 29, 2010 Report Share Posted December 29, 2010 Right. I have results One warning. The back of the stove gets really hot. You need to put in a heat shield in front of the trunking...I'm going to fit a piece of copper plate or something to match what's on the wall. Actually, I'm lost in admiration for all this. Not only a 'do it now' attitude, but actual facts and figures! The only caveat I have is exactly what you warn about. Most precautions against excess heat relate to the back of the stove, but the top of the the flue at ceiling level can get just as hot, and any wooden or plastic ducting would need protection. Mac Link to comment Share on other sites More sharing options...
Heffalump Posted December 29, 2010 Report Share Posted December 29, 2010 Dean, can we have some pics? Link to comment Share on other sites More sharing options...
DeanS Posted December 30, 2010 Report Share Posted December 30, 2010 (edited) Dean, can we have some pics? Certainly..but once I've added the heat protection, which should be tomorrow ;-) I've had the fire running all evening, and the thermometer at the midpoint of the boat is still showing 20degrees...and thats at head level...(I've already installed the thermometer as a permanent fixture at that point). The airvent in the trunking is on floor level at this point in the boat...and the stove is miles away, so I doubt the stove is causing the heat. When you feel the air coming out the vent, it feels cool to the touch, but as someone mentioned, thats because it's below skin temp. I havent had a blazing stove all evening.......a medium heat...the coals have even almost died a few times, and I stoke it and add some coals... actually...just realized I dont have a camera on the boat at the moment..I just came down for the week. Will try take with cellphone and get them off asap. Edited December 30, 2010 by DeanS Link to comment Share on other sites More sharing options...
Alan Saunders Posted December 30, 2010 Report Share Posted December 30, 2010 Great results Dean! Thank you! Instead of just a heat-shield consider feeding your system from a tube collecting the heat from the flue. BTW, the reason there is some interest in reducing the vertical thermal gradient is because we feel more comfortable with warm feet and a cool head. Right now I have 14c at floor level and 24C at head level (sitting) with heat provided only by fin-rads. Ideally, my feet would be warmer than my head and I would be comfortable with a much lower aversge temperature. Alan Link to comment Share on other sites More sharing options...
Robin2 Posted December 30, 2010 Author Report Share Posted December 30, 2010 (edited) IME when using a fan to circulate warm air the draught created makes me feel colder. Yes, I was very conscious of this. My first attempt was to blow air from the kitchen past the bathroom and into the bedroom - a distance of about 2 metres. When the fan was on full power it caused quite a draught when reading in bed so was promptly switched off. In any case the fan just circulated air between the kitchen and bedroom and did not bring it near the stove. For that reason I had almost given up until the Ecofan broke. My present setup has the fan blowing much more slowly and through a duct of over 5 metres so the airflow into the bedroom is barely perceptible. However when it is running all the time it works well. Edited December 30, 2010 by Robin2 Link to comment Share on other sites More sharing options...
DeanS Posted December 31, 2010 Report Share Posted December 31, 2010 (edited) In case this helps anyone..here is a breakdown (in the absence of photos) of what I installed to move hot air from above my firestove to floor level further down the boat. The items I purchased were these: http://www.maplin.co.uk/Module.aspx?ModuleNo=1806 - 120mm 12Volt fan http://www.maplin.co.uk/Module.aspx?ModuleNo=1676 - LH23A - Enclosure for the fan http://www.wickes.co.uk/Squareline-Downpipe-25m/invt/158861 - Black airflow square piping http://www.wickes.co.uk/invt/163573?WT.ac=SP010002 - Metal Channel I cut the lid on the enclosure box shorter to fit the fan on the box. I cut a 70x70 hole in the same box and slid the box on top of the airflow square tubing. I ran the tubing the safest path from above the firestove, down to the floor level and along the length of the boat, drilling some 12mm holes at different points, depending on where you want more/less air to blow out. The Metal Channel was added to cover the plastic tubing as it ran down the side of the firestove, just in case the heat got too much. During tests, I put some wood in front of the square piping and it was fine, but I think the metal channel will work fine. (only £4 a length) I sprayed it black with heat resistant spray paint to match the piping. The idea was simple, but the tricky bits were finding the best route for the piping(keep it away from the heat as much as you can. I only have it passing the heat in one place..about 20cm away from the stove, which is where I added the metal channel. ) The idea of pumping warmer air from the top ceiling level of the fire, to the floor level along the length of the boat, just seems to be a good idea for circulation and equalisation of temperatures. (No need to have a roaring fire at one end trying to get heat to the other end...). My personal opinion is that it did make a difference....before I was feeling that the fire was a bit useless as it only heated up one end of the boat, and if you fired it up, you couldnt sit near it.....whereas this system lets you have a less fierce fire in one place and a better overall heat. I am sure a back boiler solution would give a similar result, but might not create as much air circulation... end of my story:)...destined to the forum archives for some other poor sod who has a limited budget and a cold boat. The only downside of my story is that my fan is quite loud...but I found a way to fix it. I just turned the tv volume up much louder You could probably quiet the fan using various methods....for another thread. Edited December 31, 2010 by DeanS Link to comment Share on other sites More sharing options...
Top cat Posted January 1, 2011 Report Share Posted January 1, 2011 I've been using a couple of fans wired in series for quite a while and find they move the hot air about quite efficiently even without a duct. Wiring the fans in series slows them down which reduces the noise. Regards TC Link to comment Share on other sites More sharing options...
marmaduke Posted January 1, 2011 Report Share Posted January 1, 2011 (edited) Yes me too. The saloon of my boat is stiflingly hot at head height when the Morso has been alight for a few hours but the temperature at floor level remains stubbornly low, even with the Ecofan spinning away furiously. This is clearly caused by the fresh air blasting in through the low level air vents from outside, but the draught of air coming in seems more than I'd have expected to match the pull of the Morso flue. I think the extra cold airflow in at floor level is accounted for by the shedload of warm air flowing OUT of all the mushroom vents in the ceilings. The big thermal gradient from floor to ceiling (despite the Ecofan) supports this airflow and extremely cold weather outside exaggerates the effect. Consequently I have been thinking about how ineffective the Ecofan is and how I can get rid of the huge vertical temperature gradient. I've been thing along the lines of a vertical tube (or two) from ceiling to floor with a 12v PC fan in each. Something to stir up the air a bit more effectively than an Ecofan. Despite anecdotal opinion the Ecofan has little effect on creating air turbulence (in our boat at least). I've established this using the smoke pen I use for testing boiler flues for spillage. The smoke pen produces a thin continuous trail of smoke so airflows can be made visible. Putting the smoke pen in the airflow from the Ecofan shows the air from it moves diagonally across and up at about 45 degrees, and this airflow completely peters out around 1m away from the fan. Pretty feeble really. Has anyone tried vertical pipes to pump hot air from ceiling level down to the floor? Or maybe the pipes are not necessary, just fans pointing downwards. Or fans at floor level pointing UP....? Has anyone done any experimenting along these lines? Mike This is exactly my problem too. Stove kicks out plenty of heat, but it all goes up and stays there, while the floor is still bloody freezing. Very interested in any methods to combat this, perhaps it will have to be some sort of duct system around the boat. What did they do a hundred years ago though? Edited January 1, 2011 by marmaduke Link to comment Share on other sites More sharing options...
Amicus Posted January 1, 2011 Report Share Posted January 1, 2011 Just a thought, wood it not be better to do this stuff the other way round? Install the fan in the cold part, i.e. right aft and low down, have the system push cold/dense air forward to exit close to the heat source. Idda thought the fan would work better in the dense air and aft is, usually, where the power source is situated. Link to comment Share on other sites More sharing options...
DeanS Posted January 1, 2011 Report Share Posted January 1, 2011 Just a thought, wood it not be better to do this stuff the other way round? Install the fan in the cold part, i.e. right aft and low down, have the system push cold/dense air forward to exit close to the heat source. Idda thought the fan would work better in the dense air and aft is, usually, where the power source is situated. My brain says....push the hot air to where you want it....rather than...push the cold air away from where you dont want it There is also the 3rd dimension of putting the fan...at the end of the ducting...sucking from the ducting, and blowing outwards...whereas I have it at the hot side blowing into the ducting, and the end of the ducting is open to the room. The method I used, as suggested by someone else at the beginning of the thread was to shift hot air from one place to another. Delivering it to floor level was a concept developed during the early days of this thread, which is what I decided to do, and it worked quite well This is exactly my problem too. Stove kicks out plenty of heat, but it all goes up and stays there, while the floor is still bloody freezing. Very interested in any methods to combat this, perhaps it will have to be some sort of duct system around the boat. What did they do a hundred years ago though? This whole thread has been testing methods of doing just that. I decided to buy the goodies, install the goodies and test the goodies, and had decent results. If you make a roaring fire, you will always have stifling heat near the roof. I found that by using ducting, and an extraction fan...I no longer had to have a roaring fire...just a decent one....and the entire boat eventually equilized into an invisible airflow circulation....undetectible to the skin, but visible using a flame.... The ducting method did seem to stir up things so floor/ceiling differentials weren't as bad as before. However...anyone else on this forum who decides to copy this idea, does so at their own risk....as the results are quite relative to personal expectations. Link to comment Share on other sites More sharing options...
Amicus Posted January 1, 2011 Report Share Posted January 1, 2011 (edited) My brain says....push the hot air to where you want it....rather than...push the cold air away from where you dont want it snip Nope, you're expecting warm light air to displace cold heavy, baint goin' to 'appen Edit Cold room and a fan heater, where the best place for the heater, up high or on the floor, same thing Edited January 1, 2011 by Amicus Link to comment Share on other sites More sharing options...
bottle Posted January 1, 2011 Report Share Posted January 1, 2011 From Deans post: Delivering it to floor level was a concept developed during the early days of this thread, which is what I decided to do, and it worked quite well Link to comment Share on other sites More sharing options...
DeanS Posted January 1, 2011 Report Share Posted January 1, 2011 Nope, you're expecting warm light air to displace cold heavy, baint goin' to 'appen Edit Cold room and a fan heater, where the best place for the heater, up high or on the floor, same thing Before my ducting. Roaring Fire on. Lounge hot. Bedroom freezing. jacket on. After ducting. medium Fire on. Lounge not as hot. Bedroom not freezing. Shorts and Tshirt on. Link to comment Share on other sites More sharing options...
Offcumden Posted January 2, 2011 Report Share Posted January 2, 2011 I started reading this thread a couple of days ago and then realised that I was moored a couple of boats away from the OP. I asked Robin if I could see it in operation. With the fan running at an inaudible level, the air temperature at the fan duct read 24c and exiting at 21c. My existing fittings will dictate installing the fan level with the top of the morso and running the ducting under the gunnel ledge ending in the bedroom. My intention would be to keep the rear of the boat warmer through the day. Turning the fan off before going to to bed with the possiblity of installing a timer switch to activate the system in the morning. I wonder if it would be beneficial to install a smaller fan at the end the ducting to help extract the warm air and circlate the airflow in the bedroom? John Link to comment Share on other sites More sharing options...
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