Better than Ecofan

[Robin2]

I started a post recently about the failure of my Ecofan - probably because it overheated.

 

Rather than rush to repair it I have created a much better air circulation system for the heat from my Morso stove. I have installed a duct at roof level above the windows that carries warm air from near the Morso chimney back to the bedroom. The air is moved by a 110mm computer fan driven from the 12v supply through a 68ohm resistor and drawing 120mA. The fan is almost silent and it kept the bedroom lovely and warm the other night when the outside temperature was -11.

 

At the moment most of the duct is a temporary affair made from wallpaper. The permanent version will use two 70mm square plastic downpipes.

[DeanS]

I started a post recently about the failure of my Ecofan - probably because it overheated.

 

Rather than rush to repair it I have created a much better air circulation system for the heat from my Morso stove. I have installed a duct at roof level above the windows that carries warm air from near the Morso chimney back to the bedroom. The air is moved by a 110mm computer fan driven from the 12v supply through a 68ohm resistor and drawing 120mA. The fan is almost silent and it kept the bedroom lovely and warm the other night when the outside temperature was -11.

 

At the moment most of the duct is a temporary affair made from wallpaper. The permanent version will use two 70mm square plastic downpipes.

 

great idea. Do you think it would work if it carried hot air to the bedroom AND the back boaters cabin.. .in other words...have multiple exits like an aircon?

[BEngo]

great idea. Do you think it would work ifiit carried hot air to the bedroom AND the back boaters cabin.. .in other words...have multiple exits like an aircon?

:

 

No reason why not. You should think about the additional losses of the longer run. That might mean taking out the resistor which I suspect the OP included to slow down and quieten the fan or you might need two fans. You will also need to make provision for balancing the system so that the warm air is shared fairly between the outlets. As the back outlet is furthest away the air will have cooled down some by the time it gets there, so 'fairly' could mean the back gets more air.

 

Depending on your engine room set up (I assume you have one as you have a boaters cabin)you might also want to think whether the duct through the engine room might need to be fire-resistant.....

 

Regards

N

[Guest]

I started a post recently about the failure of my Ecofan - probably because it overheated.

 

Rather than rush to repair it I have created a much better air circulation system for the heat from my Morso stove. I have installed a duct at roof level above the windows that carries warm air from near the Morso chimney back to the bedroom. The air is moved by a 110mm computer fan driven from the 12v supply through a 68ohm resistor and drawing 120mA. The fan is almost silent and it kept the bedroom lovely and warm the other night when the outside temperature was -11.

 

At the moment most of the duct is a temporary affair made from wallpaper. The permanent version will use two 70mm square plastic downpipes.

Excellent result. I once considered a similar idea using that flat ducting designed for venting kitchen cooker hoods. I didn't think a computer fan would have enough air flow, but your experiment has proved otherwise.

[Pretty Funked Up]

This has been done loads before. Use 120mm low rpm fans direct to 12v supply.

If you place the fan in the middle of the ducted run(sealed) it will be more effective and quiter to boot.

[Robin2]

This has been done loads before. Use 120mm low rpm fans direct to 12v supply.

If you place the fan in the middle of the ducted run(sealed) it will be more effective and quiter to boot.

 

Where does one get the fan you mentioned? Are they cheaper than computer fans? How much power do they use?

[Pretty Funked Up]

Where does one get the fan you mentioned? Are they cheaper than computer fans? How much power do they use?

 

duct

 

adjustable fan (bit pricey)

 

fan i used (but almost twice what i paid)

[owen]

I started a post recently about the failure of my Ecofan - probably because it overheated.

 

Rather than rush to repair it I have created a much better air circulation system for the heat from my Morso stove. I have installed a duct at roof level above the windows that carries warm air from near the Morso chimney back to the bedroom. The air is moved by a 110mm computer fan driven from the 12v supply through a 68ohm resistor and drawing 120mA. The fan is almost silent and it kept the bedroom lovely and warm the other night when the outside temperature was -11.

 

At the moment most of the duct is a temporary affair made from wallpaper. The permanent version will use two 70mm square plastic downpipes.

youve given me a great idea i havent started my fit out yet just insulation ballast and floor. one of the things iwas going to do was to put a slightly dropped centre to my roof to run cables for lighting and still make it accessible.So i am now thinking i might run a duct in it with openable brass vent to allow warm air into other areas the size of duct will have to be smaller so might use slim cable ducting 35mm x70mm cheers for idea though

[steelaway]

Where does one get the fan you mentioned? Are they cheaper than computer fans? How much power do they use?

 

 

 

 

EBay

[Pretty Funked Up]

EBay

 

Yeah ebay is chocker with them. type '120mm quiet' into the search and your spoilt for choice.

the reason for 120mm (or bigger)with no more than 1200rpm is they turn slowly enough to be almost silent and still have the ability to move a decent amount of air.

 

mine draw 0.12 amps

Edited December 27, 2010 by Pretty Funked Up

[Guest]

I'm surprised that blown air heating, which is effectively what we are talking about here, isn't more common on narrowboats.

It worked very well in all the newer/later caravans we had.

 

Obviously 12v power consumption would/could be an issue and the central heat source would have to be gas or diesel I guess rather than the stove (though don't see how that couldn't be adapted to provide a central heat source though).

[ditchcrawler]

I'm surprised that blown air heating, which is effectively what we are talking about here, isn't more common on narrowboats.

It worked very well in all the newer/later caravans we had.

 

Obviously 12v power consumption would/could be an issue and the central heat source would have to be gas or diesel I guess rather than the stove (though don't see how that couldn't be adapted to provide a central heat source though).

Yachts often have blown air systems likeWebasto or Eberspacher

[blodger]

Yachts often have blown air systems likeWebasto or Eberspacher

I went to sea in 50's, 60's & 70s built ships with blown air systems and they were all horrendous. The same system was better for air conditioning though.

[Guest]

I went to sea in 50's, 60's & 70s built ships with blown air systems and they were all horrendous. The same system was better for air conditioning though.

Horrendous as in inefficient?

[blodger]

Horrendous as in inefficient?

Noisy and inefficient

[Mac of Cygnet]

 

 

..........and the central heat source would have to be gas or diesel I guess rather than the stove (though don't see how that couldn't be adapted to provide a central heat source though).

 

It is actually illegal to install an extractor fan in the same room as a solid fuel stove in a domestic (ie house) situation, and not recommended even in an adjoining room. I haven't looked to see if the BSS says anything about this, but the balance of fan power and drawing power of the stove would have to be considered. Also the fact that the air would re-enter the same(ish) space ie the boat. Am I overcomplicating this?

 

Mac

[Robin2]

<snip>

 

Thanks - they are quite like what I have. I thought you might have been referring to a ventilation system fan.

[Pretty Funked Up]

It is actually illegal to install an extractor fan in the same room as a solid fuel stove in a domestic (ie house) situation, and not recommended even in an adjoining room. I haven't looked to see if the BSS says anything about this, but the balance of fan power and drawing power of the stove would have to be considered. Also the fact that the air would re-enter the same(ish) space ie the boat. Am I overcomplicating this?

 

Mac

 

I find the all the compulsory air vents and mother natures wind far more of an issue

[MtB]

I find the all the compulsory air vents and mother natures wind far more of an issue

 

 

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

[DeanS]

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

 

Since I dont have a clear space along the roof/wall join all the way down the inside of the boat(above the windows), I was actually considering sucking the hot air, with the 12V fan, and routing it down, and along floor level, the length of the boat...letting it vent into the galley,bedroom,toilet areas, at floor level. What you are suggesting, tends to confirm that this would be a good thing to do?

[MtB]

Since I dont have a clear space along the roof/wall join all the way down the inside of the boat(above the windows), I was actually considering sucking the hot air, with the 12V fan, and routing it down, and along floor level, the length of the boat...letting it vent into the galley,bedroom,toilet areas, at floor level. What you are suggesting, tends to confirm that this would be a good thing to do?

 

Yes. Warm air outlets at cold floor level will lead to a much higher comfort level than high level outlets in my opinion. My doubts about the effectiveness of your system would revolve around the fact that the temperature of the warm air you are getting from around your fire will not be that high once you start really shifting any volume of air.

 

The Webasto we have at the back of our boat delivers a hefty blast of air that actually feels HOT to the hand, yet it still takes quite a while to warm the back cabin and main bedroom.

 

I doubt the system you describe would do much heating in a hurry. On the other hand if run all the time the fire is alight I'd expect it to raise the temp of the galley and bedroom by several degrees eventually - just don't expect 'central heating' level of performance. For that, you need proper central heating i.e. back boiler, wet rads and a pump, or a Webasto/Eberspacher diesel warm air blower. If it could be done effectly with some rainwwater pipe and a PC fan then Webasto et al would soon be out of business once word got around!

 

Mike

[DeanS]

Yes. Warm air outlets at cold floor level will lead to a much higher comfort level than high level outlets in my opinion. My doubts about the effectiveness of your system would revolve around the fact that the temperature of the warm air you are getting from around your fire will not be that high once you start really shifting any volume of air.

 

The Webasto we have at the back of our boat delivers a hefty blast of air that actually feels HOT to the hand, yet it still takes quite a while to warm the back cabin and main bedroom.

 

I doubt the system you describe would do much heating in a hurry. On the other hand if run all the time the fire is alight I'd expect it to raise the temp of the galley and bedroom by several degrees eventually - just don't expect 'central heating' level of performance. For that, you need proper central heating i.e. back boiler, wet rads and a pump, or a Webasto/Eberspacher diesel warm air blower. If it could be done effectly with some rainwwater pipe and a PC fan then Webasto et al would soon be out of business once word got around!

 

Mike

 

When my Morso Squirrel has been lit for 30mins, the air at head height, anywhere within 1metre is unbreathable it is so hot. In fact I flapped a plastic storage box lid twice last night trying to move the hot air down the boat...so I'm actually quite excited about this new idea...will be testing it this week if I can get the bits... At the moment the lounge is too hot, and the rest of the boat is too cold.

[Québec]

[snip] 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. ..... Has anyone done any experimenting along these lines?

Mike

 

Another 'me too'...and certainly thinking along those lines i.e. how to get warm air circulating down to floor level.

Bought some cheap thermometers just to see what was happening inside the boat.

40' trad. 4kw stove at front into open living/kitchen area, then wall of bathroom across the boat leaving short narrow corridor to rear bedroom area.

 

Stove well fired up + Ecofan spinning fast + low vents in front doors next to stove + 4 mushroom vents open

 

External temperature -10C

 

Internal temperature

At 1.5m/5' height went from 23C near stove to 20C in kitchen area to 10C in bedroom and 6C at rear doors.

At floor level went from 6C near stove to 3C in kitchen to 1C in bedroom.

 

Temperature first thing in the morning after stove closed down for the night:

At 1.5m/5' height went from 11C near stove to 8C in kitchen area to 4C in bedroom and 2C at rear doors.

At floor level went from 2C near stove, 0C in kitchen, -2C in bedroom.

 

Have shifted from Eco 'fan' to sceptic, and am looking for better ways to get a much narrower heat differential between 1) floor and ceiling and 2) front and rear.

Edited December 28, 2010 by Québec

[Pretty Funked Up]

I found the best way to position the fans was blowing straight down on an outside wall, aiding natural convections, with about 100mm gap between fan and ceiling.

 

Have a play about, they can be very effective when you find the right spot (something I suspect will be indiviual to a boat and everyone will have to find their own 'perfect spot')

 

I now have pumped hot water from back boiler and dont use the fans at all now, theyre loitering around waiting for the next 'project'

[Robin2]

youve given me a great idea i havent started my fit out yet just insulation ballast and floor. one of the things iwas going to do was to put a slightly dropped centre to my roof to run cables for lighting and still make it accessible.So i am now thinking i might run a duct in it with openable brass vent to allow warm air into other areas the size of duct will have to be smaller so might use slim cable ducting 35mm x70mm cheers for idea though

 

I doubt if 35x70 would be big enough unless you have a powerful (= noisy) fan. I have settled on 2 x 70mm square which is 98 sq cm. I would prefer 120mm diam duct which would be 113 sq cm but it would be too bulky. Also a single duct would be better than a pair because there would be less surface area to cause drag.

 

I'm surprised that blown air heating, which is effectively what we are talking about here, isn't more common on narrowboats.

It worked very well in all the newer/later caravans we had.

 

Obviously 12v power consumption would/could be an issue and the central heat source would have to be gas or diesel I guess rather than the stove (though don't see how that couldn't be adapted to provide a central heat source though).

 

I had an Eberspacher and then a Wallas blown air system on a previous boat. They worked well but the Eberspacher motor brushes wore out and cost £500 to replace (new motor) - hence the change to the Wallas (same issue but cheaper parts). They burn diesel to create the heat and they do use quite an amount of electricity for their powerful fans. What I am doing now is simply circulating the existing heat within the boat and the current draw is about 130mA. My plan is to have the fan running 24x7.

 

It is actually illegal to install an extractor fan in the same room as a solid fuel stove in a domestic (ie house) situation, and not recommended even in an adjoining room. I haven't looked to see if the BSS says anything about this, but the balance of fan power and drawing power of the stove would have to be considered. Also the fact that the air would re-enter the same(ish) space ie the boat. Am I overcomplicating this?

 

Mac

 

I am not extracting air to the outside of the boat, or outside the "room" in which the stove is burning. The whole boat is effectively one room.

 

There have been a few comments about cold air at low level and my system does not really address that. I suspect it will be difficult to solve that problem without more powerful fans to move air through longer curved ducts. Blocking off or re-directing draughts would be my first line of attack. Also, someone correctly mentioned that drawing a larger volume of air from the ceiling near the stove would reduce the temperature.

 

I found the best way to position the fans was blowing straight down on an outside wall, aiding natural convections, with about 100mm gap between fan and ceiling.

 

Have a play about, they can be very effective when you find the right spot (something I suspect will be indiviual to a boat and everyone will have to find their own 'perfect spot')

 

I now have pumped hot water from back boiler and dont use the fans at all now, theyre loitering around waiting for the next 'project'

 

Out of curiosity, how much current does the circulation pump use, and is it running continuously?