Jump to content
Strawberry Orange Banana Lime Leaf Slate Sky Blueberry Grape Watermelon Chocolate Marble
Strawberry Orange Banana Lime Leaf Slate Sky Blueberry Grape Watermelon Chocolate Marble
Sign in to follow this  
Maudesmaster

Linking Eberspächer and exhaust heat exchange

Featured Posts

I will be heating boat and water via Eberspächer hydronic 5 to 5 radiators and 1 coil in calorifier but would also like to heat via an exhaust heat exchanger I have fabricated on the Gardner 3LW  which will go to second coil in calorifier How can I link the Heat exchanger and Eberspächer to heat the Radiators and hot water 

5AF717DB-7D30-4DBF-8A4E-009CCE945909.png

B4E11CD9-B619-4026-A2EB-88673A10DAEE.jpeg

9DECA792-7981-44C0-AE02-4776E5C52497.jpeg

Share this post


Link to post
Share on other sites

Interesting idea ... I'm curious to see what feedback you get from people who know more about heating/plumbing than I do.  We do not have any connection between the engine and hot water system so rely on an Eberspächer.  The fall back option is a 1kW immersion heater powered by a Travel Pack.

Share this post


Link to post
Share on other sites

Interesting. Looks well made.

 

It seems complicated? I assume your expansion tanks are accumulators. I do not think they are necessary in the hot feed from the boiler and the heat exchanger to the clarifier coils, the expansion duty should be accomplished by the header tank.

Your boiler circuit and your exhaust heat recovery circuit will presumably have pumps? 

Are you sure you can recover enough energy from the exhaust to heat the rads as well as the clarifier? Our 3LW exhaust does not get very hot at causing speeds. Also if that is just a plain can wrapped around the exhaust pipe the heat exchange area looks very low, especially given the relatively high exhaust gas flow velocity.

Conversely you need to avoid letting the exhaust get too cool, you do not want the exhaust gases condensing and either being retained in the exhaust or blowing out of the top of the exhaust (think wet black soot, but also somewhat acidic depending on fuel sulphur content)

I have toyed with the idea of recovering heat from our engine but would use a heat exchanger in the cooling system pipework to the skin tank, that is where most of the heat discharge from the engine is going and currently its all thrown away. This approach is a lot simpler, no second head tank, single calorifier coil needed, no second pump etc. 

 

 

 

Edited by jonesthenuke
typos!

Share this post


Link to post
Share on other sites
On 13/02/2019 at 12:17, Boater Sam said:

No reason why not as far as I can see. But then today I have been accused of talking rubbish.

 

11 hours ago, jonesthenuke said:

Interesting. Looks well made.

 

It seems complicated? I assume your expansion tanks are accumulators. I do not think they are necessary in the hot feed from the boiler and the heat exchanger to the clarifier coils, the expansion duty should be accomplished by the header tank.

Your boiler circuit and your exhaust heat recovery circuit will presumably have pumps? 

Are you sure you can recover enough energy from the exhaust to heat the rads as well as the clarifier? Our 3LW exhaust does not get very hot at causing speeds. Also if that is just a plain can wrapped around the exhaust pipe the heat exchange area looks very low, especially given the relatively high exhaust gas flow velocity.

Conversely you need to avoid letting the exhaust get too cool, you do not want the exhaust gases condensing and either being retained in the exhaust or blowing out of the top of the exhaust (think wet black soot, but also somewhat acidic depending on fuel sulphur content)

I have toyed with the idea of recovering heat from our engine but would use a heat exchanger in the cooling system pipework to the skin tank, that is where most of the heat discharge from the engine is going and currently its all thrown away. This approach is a lot simpler, no second head tank, single calorifier coil needed, no second pump etc. 

 

 

 

 

Thank you for replies 

The boat has not been floated as yet, when I first installed and ran the engine with skin tanks full the pipe work to and from skin tanks after 1 hour running the was only luke  warm whereas the exhaust was very hot 

My thinking was to try this idea out using only a small can with the flanges welded around the exhaust so water did not boil or cool the exhaust gasses too much I can modify the exhaust at a later date 

Can I tee into the pipe work so that when engine is running it heats the radiators

 

 

12 hours ago, GRLMK38 said:

Interesting idea ... I'm curious to see what feedback you get from people who know more about heating/plumbing than I do.  We do not have any connection between the engine and hot water system so rely on an Eberspächer.  The fall back option is a 1kW immersion heater powered by a Travel Pack.

 

On 16/03/2012 at 11:20, Rick-n-Jo said:

If you are anywhere near Saul Junction (Glos & Sharpness Canal) and would like to see a Heritage Compact (2 hob but single burner version) installed in a nb, let me know.

 

We have very good local service/installation engineer co. here who are happy to work on boats - not all are, but I have learned to change the burner nozzle myself, it's not a particularly difficult job and spares can be had online for less than a tenner. The jet on the lower output burner such as you would fit on a boat is quite tiny, so can get partially blocked or coked up, also easily damaged by mishandling. I would recommend Danfoss nozzle, since fitted has given no further trouble.

 

These cookers really are well insulated, exess heat has never been a problem for us. (We did make sure to have a side hatch next to the cooker in case, but have hardly ever felt the need to have it open) From cold it will boil a kettle in 5-10 mins, oven temp in 20. The single burner is obviously a compromise between cooking and water heating/central heating, compared to the two burner models, but is easy to manage with a simple plumbing system, and is obviously cheaper for buying, servicing and I would guess fuel.

 

We live aboard and keep the boat warm but not roasting hot (put on woolies if its frosty, turn heating off at night) and have found our range to be pretty economical on fuel - and so easy compared to wood/coal/gas

 

You do of course need a 240V supply when its running and I would only consider installing in a boat with a well designed ac system i.e. good inverter and battery spec and adequate charging provision. It uses about 100w when firing but once up to temp only fires fo about 5-10% of time thanks to good insulation.

 

Basically, we likes it :)

 

Rick

 

Share this post


Link to post
Share on other sites

I would have thought that a 3LW would not produce enough heat to make this run efficiently. I think that Jones the Nuke is on the right track when mentioning the condensation and  black soot which is sure to follow. We always fit a decent thermostat system to the engines (dozens and dozens over the years). This enables the engine to run at the optimum  temperature which narrowboat engines seldom do and, once warmed up to supply hot water to one of the calorifier coils. This always works well. The heat loss through the calorifier system is usually  significant with the result that the engine stat seldom fully opens and it is unusual for cooling water to circulate through the skin tank except when thrashing up a river etc.

 The other thing to bear in mind is the need to prevent circulation through the engine related part of the circuit when the engine is off. Engines make splendid heat sinks and will cool the water in the calorifier overnight.

Share this post


Link to post
Share on other sites
2 hours ago, Maudesmaster said:

The boat has not been floated as yet, when I first installed and ran the engine with skin tanks full the pipe work to and from skin tanks after 1 hour running the was only luke  warm whereas the exhaust was very hot 

 

You were presumably running the engine without any load, so its not really surprising the cooling water did not get hot. You need a thermostat fitted and for the engine to be doing some work to generate a resonable amount of heat.

Share this post


Link to post
Share on other sites

Thank you for all replies feeling a bit sad now

I do have the bowman header tank on the cooling system which was all a bit of a mish mash as as the engine came from a fishing boat 

I had to buy a new thermostat housing and re route the pipe work so if all goes t!ts up I can re route through the heat exchanger on the bowman header tank, what would have been great if bowman made them for the Gardner would have been a manifold heat exchanger perhaps 

16 hours ago, jonesthenuke said:

Interesting. Looks well made.

 

It seems complicated? I assume your expansion tanks are accumulators. I do not think they are necessary in the hot feed from the boiler and the heat exchanger to the clarifier coils, the expansion duty should be accomplished by the header tank.

Your boiler circuit and your exhaust heat recovery circuit will presumably have pumps? 

Are you sure you can recover enough energy from the exhaust to heat the rads as well as the clarifier? Our 3LW exhaust does not get very hot at causing speeds. Also if that is just a plain can wrapped around the exhaust pipe the heat exchange area looks very low, especially given the relatively high exhaust gas flow velocity.

Conversely you need to avoid letting the exhaust get too cool, you do not want the exhaust gases condensing and either being retained in the exhaust or blowing out of the top of the exhaust (think wet black soot, but also somewhat acidic depending on fuel sulphur content)

I have toyed with the idea of recovering heat from our engine but would use a heat exchanger in the cooling system pipework to the skin tank, that is where most of the heat discharge from the engine is going and currently its all thrown away. This approach is a lot simpler, no second head tank, single calorifier coil needed, no second pump etc. 

 

 

 

 

2 hours ago, David Mack said:

 

You were presumably running the engine without any load, so its not really surprising the cooling water did not get hot. You need a thermostat fitted and for the engine to be doing some work to generate a resonable amount of heat.

 

3 hours ago, steamraiser2 said:

I would have thought that a 3LW would not produce enough heat to make this run efficiently. I think that Jones the Nuke is on the right track when mentioning the condensation and  black soot which is sure to follow. We always fit a decent thermostat system to the engines (dozens and dozens over the years). This enables the engine to run at the optimum  temperature which narrowboat engines seldom do and, once warmed up to supply hot water to one of the calorifier coils. This always works well. The heat loss through the calorifier system is usually  significant with the result that the engine stat seldom fully opens and it is unusual for cooling water to circulate through the skin tank except when thrashing up a river etc.

 The other thing to bear in mind is the need to prevent circulation through the engine related part of the circuit when the engine is off. Engines make splendid heat sinks and will cool the water in the calorifier overnight.

 

4 hours ago, Maudesmaster said:

 

 

Thank you for replies 

The boat has not been floated as yet, when I first installed and ran the engine with skin tanks full the pipe work to and from skin tanks after 1 hour running the was only luke  warm whereas the exhaust was very hot 

My thinking was to try this idea out using only a small can with the flanges welded around the exhaust so water did not boil or cool the exhaust gasses too much I can modify the exhaust at a later date 

Can I tee into the pipe work so that when engine is running it heats the radiators

 

 

 

 

 

 

Share this post


Link to post
Share on other sites

All is not lost, it could be modified to enable you to inject exhaust dye like the Red Arrows?

  • Happy 1
  • Haha 1

Share this post


Link to post
Share on other sites
3 hours ago, steamraiser2 said:

I would have thought that a 3LW would not produce enough heat to mI would have thought that a 3LW would not produce enough heat to make this run efficientlyake this run efficiently. I think that Jones the Nuke is on the right track when mentioning the condensation and  black soot which is sure to follow. We always fit a decent thermostat system to the engines (dozens and dozens over the years). This enables the engine to run at the optimum  temperature which narrowboat engines seldom do and, once warmed up to supply hot water to one of the calorifier coils. This always works well. The heat loss through the calorifier system is usually  significant with the result that the engine stat seldom fully opens and it is unusual for cooling water to circulate through the skin tank except when thrashing up a river etc.

 The other thing to bear in mind is the need to prevent circulation through the engine related part of the circuit when the engine is off. Engines make splendid heat sinks and will cool the water in the calorifier overnight.

That was my first thought. I know exhausts can, under load, get very hot, even glow, but temperature and heat are different things that are often confused so I suspect the exhaust heat exchange is way too small and even if larger may not work very well. I think the exhaust heat exchanger circuit will need pumping unless the hot pipe runs at roof level and it is at least 22mm in diameter but 28mm is better.

 

The easiest way to get either to heat the radiators would probably be to connect them in series and accept the loss of heat from whichever unit was not heating. Otherwise   a manual change over valve to direct either output to the rads and single calorifier coil wound probably work.

Share this post


Link to post
Share on other sites

The other thing to consider is whether you will need heating when the engine is running? If this is an engine within an engine room (ours is) then when you are going along the whole boat will get warm, in fact in the summer you need to maximise ventilation to keep ambient temperatures inside the boat sensible. In winter its a case of closing windows and hatches until the temperature is sensible. When you moor up you have a third of a ton of hot engine to warm up the boat, close the doors and you have free heating for a few hours. Now if you choose to run the engine when moored to charge batteries, recovery of exhaust heat may be of use as it takes a long time to heat up the block of a 3LW, but you exhaust will warm up far quicker. The down side is that the engine load will be low unless you have huge alternators etc so the gain may be modest.

 

Don't be put off by the comments, its looking like a good installation and you may get some benefit from it.

Share this post


Link to post
Share on other sites

I do have 2 120 amp alternators running off 70mm pulleys to a 14” crank pulley 1 of which I may change to a lesser one for starter batteries It’s a big learning curve however I would never take on a total fit out again 10 hour days and sleepless nights 

thank you all for your input will let you know how it’s all gone in September when hoping to launch Maud of the marshes 

Share this post


Link to post
Share on other sites
1 hour ago, Maudesmaster said:

I do have 2 120 amp alternators running off 70mm pulleys to a 14” crank pulley 1 of which I may change to a lesser one for starter batteries It’s a big learning curve however I would never take on a total fit out again 10 hour days and sleepless nights 

thank you all for your input will let you know how it’s all gone in September when hoping to launch Maud of the marshes 

Keep the two alternators with the pulleys and link the batteries with a SmartBank or equivalent, that way you have more usable domestic capacity and better charging.

(Oh and yes, I can imagine its a lot of work!, worth it in the end though)

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.