heating

[AlanH]

Sounds a lot simpler to me! (How long's your boat & do you mean your CH is a separate diesel-fired system?)

 

The other factor to take into account is how well insulated the boat is. If it is you might be able to get away with an eco-fan and none of this backboiler/radiator malarky.

 

My 42' boat has the stove at the front, bedroom at the back and no partitions. The only bit that gets really cold is the bathroom where the door is usually shut and the window open but leaving the door open soon warms it up. We don't like warm bedrooms anyway but ours is usually warm enough an hour or so after lighting the fire. Our problem these days is keeping the boat cool enough when the fire is going. Last Sat we were sat with the front doors half open and the fire shut right down. We have a catalytic gas heater (illegal to fit one now I believe) opposite the bed but we have never used it.

Ecofan is a waste of money. I've put a joss stick in front of ours and the smoke goes straight up. We had a pipe smoking friend on board and his smoke just hung around with no sign of circulating. I think that those who claim a benefit from them are merely trying to justify the expense of buying one. How on earth can a motor rated at 10mA produce enough power to circulate air throughout a boat?

[Chris J W]

Ecofan is a waste of money. I've put a joss stick in front of ours and the smoke goes straight up. We had a pipe smoking friend on board and his smoke just hung around with no sign of circulating. I think that those who claim a benefit from them are merely trying to justify the expense of buying one. How on earth can a motor rated at 10mA produce enough power to circulate air throughout a boat?

 

Tried that with mine, joss stick and ciggie smoke ... and find it very theraputic to watch the patterns the smoke caught in the makes as it whirls away. So, no problem with mine!

[tomandsophie]

Two things -

1. Our Ecofan was worth every penny. It makes a big difference to the distribution of heat, particularly regarding eliminating 'hotspots' around the stove and at the ceiling.

2. Our Squirrel backboiler and radiator system is well worth having. The radiators don't get very very hot but they provide very welcome background heat in the bedroom. But the best thing about it is that for about 7 or 8 months of the year we get free hot water for showers (and the rest of the year it is free but provided by the sun instead). Brilliant.

[colin loach]

Two things -

1. Our Ecofan was worth every penny. It makes a big difference to the distribution of heat, particularly regarding eliminating 'hotspots' around the stove and at the ceiling.

2. Our Squirrel backboiler and radiator system is well worth having. The radiators don't get very very hot but they provide very welcome background heat in the bedroom. But the best thing about it is that for about 7 or 8 months of the year we get free hot water for showers (and the rest of the year it is free but provided by the sun instead). Brilliant.

Hi all, I have decided to go with a gravity system with one rad opposite the bathroom which is next door the bedroom and a header tank, not sure where to install the tank and should I connect the boiler to the chlorifier, or will this make me loose heat from the rad. Colin.

[chris w]

I have no experience of gravity-fed systems so have no idea how well it will work with a calorifier but, in general, the boiler has a finite heat output. If you are delivering heat to a rad and then add another rad or calorifier etc then the first rad and the boiler itself will run cooler (or less hot!).

 

Chris

[blackrose]

Hi all, I have decided to go with a gravity system with one rad opposite the bathroom which is next door the bedroom and a header tank, not sure where to install the tank and should I connect the boiler to the chlorifier, or will this make me loose heat from the rad. Colin.

If you want a calorifier running off your backboiler you're better off with a pumped system. It can be done on thermocycling but it gets a bit more complicated and you'll need a calorifier with a wide bore coil, otherwise a convection/gravity fed system won't be able to circulate. Yes, you can only produce the amount of heat that your backboiler is rated at, so if you install a calorifier this will take some of the heat from the rest of system - at least until the water heats up.

 

For header tank positioning read my long post above.

 

Mike

[tomsk]

Lot of long-winded self-contradictory posts. please speak to someone who knows what they are on about rather than rely on a load of contentious and muddled mumbo-jumbo.

[blackrose]

Lot of long-winded self-contradictory posts. please speak to someone who knows what they are on about rather than rely on a load of contentious and muddled mumbo-jumbo.

 

And could you also explain to Colin the criteria one would use to judge whether someone actually knows what they're talking about on this subject?

 

I've spoken to qualified plumbers who had no idea about thermocycling systems because they never install them.

 

I'm just trying to help the guy and I've freely admitted when I was unsure of something or when I was wrong. Of course you're free to criticise but if this is a genuine criticism rather than just another snide dig, then can you tell us exactly what you think is contradictory, contentious & muddled as this might contribute to the discussion.

 

Part of the idea of this forum is about thrashing out ideas and getting to the bottom of things. What works on one boat may not work on another and we all have our own particular preferences. Few contributors have definitive answers to many of the questions posed, but since you seem qualified to conclude that we're all talking mumbo-jumbo then you obviously have a vast wealth of knowledge on this subject. So instead of just criticising why not enlighten us?

Edited March 4, 2008 by blackrose

[stuart]

Heres another idea for you which I wish I'd installed...

 

Use the engine calorifier connections to run a rad in the bathroom. In the spring/summer whilst cruising the bathroom will be heated and this allows you to try washing and wet towels. You wont want to run the solid fuel stove during this time as the boat will be too hot!

[BlueStringPudding]

Heres another idea for you which I wish I'd installed...

 

Use the engine calorifier connections to run a rad in the bathroom. In the spring/summer whilst cruising the bathroom will be heated and this allows you to try washing and wet towels. You wont want to run the solid fuel stove during this time as the boat will be too hot!

 

That's a good idea. How feasible is that retrospectively?

[colin loach]

. I would like to thank everyone for there comments, and you all have give some good ideas, at the end of the day its up to me which I choose. If it wasn’t for your response I would have no choice to pick from. I will just run the rad from the boiler because we are only there weekends and we don’t use that much gas. I will run the chlorifier from the engine when we go on holiday. Mike not sure what you mean about the header tank, I don’t want condensation. Can it be a sealed unit that just vents to outside. The header tank has got to go in a cloths cupboard to gain height because I have a cruiser stern and I would not get enough height in the engine room to put the header tank. Colin.

[blackrose]

. I would like to thank everyone for there comments, and you all have give some good ideas, at the end of the day its up to me which I choose. If it wasn’t for your response I would have no choice to pick from. I will just run the rad from the boiler because we are only there weekends and we don’t use that much gas. I will run the chlorifier from the engine when we go on holiday. Mike not sure what you mean about the header tank, I don’t want condensation. Can it be a sealed unit that just vents to outside. The header tank has got to go in a cloths cupboard to gain height because I have a cruiser stern and I would not get enough height in the engine room to put the header tank. Colin.

 

If you T the header tank off from the highest point on the upper run the entire system will be self-bleeding. Many people have header tanks which are not vented outside and they don't have a problem with condensation because the tank is far enough away from the stove that the water in the header tank gets warm but not hot. The highest point on my system is only about 10ft from the stove so the water in my header tank gets quite hot and I was worried that it would produce water vapour & condensation in the boat (although I never saw any evidence of this).

 

My header tank is an old plastic Mercedes coolant reservior (about 2 litre volume). It had a plastic cap on the top which I left off, but just to be on the safe side I connected the hole in the top to a piece of hose and then to a skin fitting in the side of the boat to vent any moisture outside.

 

You'll have to look around for a suitable header tank. Household ones are a bit too big and have open tops with lids that just sit on top. Some chandleries sell stainless steel tanks but they're expensive (about £70) and the disadvantage is that you can't see the water level at a glance. Plastic car radiator/coolant reserviors are the best in my opinion but you may struggle to find one big enough. You need about 2 liters minimum really so that you can have it about a quarter full cold and the water still has room to expand when it gets hot. Have a look on ebay and breakers yards - perhaps you could find one from a lorry?

 

Hope that makes sense.

 

Mike

 

Edit: If I remember I'll post a picture of my header tank on this thread tomorrow so you can see what I'm talking about.

Edited March 4, 2008 by blackrose

[chris w]

What about a header tank from a Webasto? They're plastic and about 5 litres at a guess. You might find one on Ebay?

 

Chris

[blackrose]

What about a header tank from a Webasto? They're plastic and about 5 litres at a guess. You might find one on Ebay?

 

Chris

 

Perfect, or from an erbespacher.

[colin loach]

What about a header tank from a Webasto? They're plastic and about 5 litres at a guess. You might find one on Ebay?Chris

Hi all, I have seen some header tanks on eBay so just one more question, hope you don’t mind. Do I vent the tank out the side or on the top so when it rains it keeps the tank toped up. Thanks Colin.

[blackrose]

Hi all, I have seen some header tanks on eBay so just one more question, hope you don’t mind. Do I vent the tank out the side or on the top so when it rains it keeps the tank toped up. Thanks Colin.

If I were you I wouldn't vent the tank at all just yet Colin. Make sure the top is left open and see how it works first. You don't want to put holes in your boat unless you have to.

 

If you think the water in the tank is getting hot and causing humidity then vent it. I did mine out the side. You could do it through the roof but I reckon you might end up with crap in the tank. Topping up is only necessary very occasionally, I've topped mine up 3 or 4 times in two years so it's not much of a chore.

 

You can buy these digital thermometers quite cheaply which are always useful on a boat. Some of them measure humidity too and with one of these you could check to see if it's more humid in the room with the header tank than the rest of the boat. If it's much more humid then you can vent the tank, otherwise don't bother. Have a look at this one. http://www.maplin.co.uk/Module.aspx?Module...ter&doy=5m3

 

Sorry I forgot to grab the digital camera from work but I'll try to remember tommorrow or Friday and will post that picture.

 

Don't hesitate to ask questions - that's what the forum's for.

Edited March 5, 2008 by blackrose

[colin loach]

Thanks Mike, that dose not sound like mumbo jumbo to me.the header tank is well away from the heater and left from the last rad so it might not get hot at all. look forward to seeing the photos.Thanks Mike, that dose not sound like mumbo jumbo to me.the header tank is well away from the heater and 15ft from the last rad so it might not get hot at all. look forward to seeing the photos

[tomsk]

And could you also explain to Colin the criteria one would use to judge whether someone actually knows what they're talking about on this subject?

 

I've spoken to qualified plumbers who had no idea about thermocycling systems because they never install them.

 

I'm just trying to help the guy and I've freely admitted when I was unsure of something or when I was wrong. Of course you're free to criticise but if this is a genuine criticism rather than just another snide dig, then can you tell us exactly what you think is contradictory, contentious & muddled as this might contribute to the discussion.

 

Part of the idea of this forum is about thrashing out ideas and getting to the bottom of things. What works on one boat may not work on another and we all have our own particular preferences. Few contributors have definitive answers to many of the questions posed, but since you seem qualified to conclude that we're all talking mumbo-jumbo then you obviously have a vast wealth of knowledge on this subject. So instead of just criticising why not enlighten us?

 

Yes, yes very true... Ok who do I invoice.

[magnetman]

I have installed 3 different thermosyphon heating systems in narrow boats. They work. The essentials are: 28mm flow pipe rises immediately to highest point in system and is vented through the roof. From there the pipework goes DOWN for the rest of the primary circulation and back to the boiler. Header tank teed to return pipe to keep it cool. Tee rads off primary circuit as desired.

[colin loach]

When you say t off the header tank dose that mean you t off at bottom of tank and go back to the boiler on the return, and the vent comes out at the top of the tank through the roof. Colin.

[blackrose]

I have installed 3 different thermosyphon heating systems in narrow boats. They work. The essentials are: 28mm flow pipe rises immediately to highest point in system and is vented through the roof. From there the pipework goes DOWN for the rest of the primary circulation and back to the boiler. Header tank teed to return pipe to keep it cool. Tee rads off primary circuit as desired.

 

In general I agree, the system will work best if the main run goes immediatly to the highest point and then very gently slopes downhill all the way to the end of the top run and then continues downhill back along the return to the backboiler. I didn't know about venting through the roof - this is presumably to bleed the system? My header tank vents from the highest point and is vented through the side so the system is self bleeding. When I had the header tank Td off from the return run the system made a lot of noise

 

Also I thought the Squirrel had 22mm outlets from the backboiler? (I could be wrong)

 

Anyway, I'm going to post a couple of pictures this evening.

 

Mike

[colin loach]

Thanks Mike, its better for me if I can see some pictures

[ChrisPy]

In general I agree, the system will work best if the main run goes immediatly to the highest point and then very gently slopes downhill all the way to the end of the top run and then continues downhill back along the return to the backboiler. I didn't know about venting through the roof - this is presumably to bleed the system? My header tank vents from the highest point and is vented through the side so the system is self bleeding. When I had the header tank Td off from the return run the system made a lot of noise

 

Also I thought the Squirrel had 22mm outlets from the backboiler? (I could be wrong)

checked mine today, looks like about 1" bore screwed piping.

 

my vent is a 15mm riser fitted immediately behind the Morso - it will vent off bubbles of steam, or whatever, before they can get into the system.

[magnetman]

My reason for external venting is in case of boiling, caused by leaving the fire door open for too long - i'd prefer steam to be ejected immediately outside the boat rather than in the living area. My current system is internally vented (will be external) and when it boiled over it scared the - out of me.

[blackrose]

Here are a couple of pictures.

 

The highest point of the system where it Ts off to the header tank. (This makes the entire system self-bleeding)

 

The header tank which is vented outside. I was told this 2 litre tank would be too small for my 20 litre system but it's fine.

When it's cold the water level is right at the bottom of the tank and when it's hot the water level rises to about a third of the way up. Eventually this lot will be inside a cupboard.

 

The second (and final) radiator which is connected at all points. The main run goes right around the last rad and all 90 degree bends are done with 2 x 135 degree joints to help circulation. As you can see it took me a few goes to get the holes through that bulkhead in the right places!

Edited March 7, 2008 by blackrose