Stovax Brunel

[far fetched]

Hi,

 

I've just had a back boiler fitted to my Stovax Brunel 1a. I'm still struggling with the water heating capacity and experimenting with different configurations, but I'm also not very happy with the fire itself.

 

Without the boiler it was a raging monster and needed little attention - either via the air intake settings, or in terms of refuelling. The boat had been sold to me with stove and radiators already fitted but without a boiler of any sort. It seemed logical, and not too expensive, to connect them by exploiting the stove's capacity to take a back boiler.

 

I'm regretting this already. The fire has become a bugger to keep going. Wood must chopped right down to 1inch sticks. Coal can easily extinguish the fire without careful tending. It seems to need refuelling every 15 or 20 minutes and dies completely within a couple of hours left to its own devices. Even a fully established fire generates only a fraction of the temperatures I was achieving prior to the modification.

 

Some of this must be due to the cooling effect of the boiler, but I'm also wondering whether I'm losing more heat up the flue since the removal of the top. baffle.

 

I can't go through the winter like this. Unless I can find a way of making it work for me I'll have to remove the bolier and rip out the fittings and restore to its previous incarnation as a mini inferno. And kiss goodbye to £500 in the process.

 

Any suggestions?

 

Mike Coll

[Proper Job]

Hi,

 

I've just had a back boiler fitted to my Stovax Brunel 1a. I'm still struggling with the water heating capacity and experimenting with different configurations, but I'm also not very happy with the fire itself.

 

Without the boiler it was a raging monster and needed little attention - either via the air intake settings, or in terms of refuelling. The boat had been sold to me with stove and radiators already fitted but without a boiler of any sort. It seemed logical, and not too expensive, to connect them by exploiting the stove's capacity to take a back boiler.

 

I'm regretting this already. The fire has become a bugger to keep going. Wood must chopped right down to 1inch sticks. Coal can easily extinguish the fire without careful tending. It seems to need refuelling every 15 or 20 minutes and dies completely within a couple of hours left to its own devices. Even a fully established fire generates only a fraction of the temperatures I was achieving prior to the modification.

 

Some of this must be due to the cooling effect of the boiler, but I'm also wondering whether I'm losing more heat up the flue since the removal of the top. baffle.

 

I can't go through the winter like this. Unless I can find a way of making it work for me I'll have to remove the bolier and rip out the fittings and restore to its previous incarnation as a mini inferno. And kiss goodbye to £500 in the process.

 

Any suggestions?

 

Mike Coll

Sorry I can't help with your current problem, but in a previous nb, we had the exact same stove (with back boiler) and it worked a treat. It ran two rad's via a gravity system.

 

The 'furnace' was a bit on the small side and could only take a couple of logs at a time. It did, on the odd occasion, extinguish itself when you banked it in over night with coal. At someone's recommendation, we experimented with different types of coal. Again, not much use to you as I can't remember which one it was, but we did find a coal that was better suited to the fire than others.

 

It may be worth experimenting with coals or ask your supplier, he may be able to help.

[Marc Harris]

We have a similar size stove with a small back boiler, and our neighbour has exactly the same stove as us without the back boiler.

 

There are definite differences between ours. The coal at the back burns very slowly as the water is keeping it cooler, but will eventually burn with a good fire going. We also seem to have to open the air vents more to produce the same heat (i am assuming this is because the fire area is a bit smaller, and the cooler coal at the back).

 

However, ours runs all night, produces plenty of heat, and we use almost the same amount of coal as our neighbours. I would think that your problem is the removal of the top baffle (as ours has one), as this would change the airflow in the stove, and send a lot more heat up the chimney?

 

Is it not possible to adapt the baffle to allow for the back boiler?

 

p.s., our stove, boiler, flue, chimney, hat and rope cost £500 delivered.... i hope you didn't pay that just for the back boiler!

 

Hope that helps in some way.

 

Marc

[far fetched]

We have a similar size stove with a small back boiler, and our neighbour has exactly the same stove as us without the back boiler.

 

There are definite differences between ours. The coal at the back burns very slowly as the water is keeping it cooler, but will eventually burn with a good fire going. We also seem to have to open the air vents more to produce the same heat (i am assuming this is because the fire area is a bit smaller, and the cooler coal at the back).

 

However, ours runs all night, produces plenty of heat, and we use almost the same amount of coal as our neighbours. I would think that your problem is the removal of the top baffle (as ours has one), as this would change the airflow in the stove, and send a lot more heat up the chimney?

 

Is it not possible to adapt the baffle to allow for the back boiler?

 

p.s., our stove, boiler, flue, chimney, hat and rope cost £500 delivered.... i hope you didn't pay that just for the back boiler!

 

Hope that helps in some way.

 

Marc

 

Thanks. The boiler itself was 130 plus 280 for pipes and stuff and 100 to the fitter. Possibly over the odds but it was the cheapest quote so I went with it.

 

I'll investigate whether there is a an adaptation that can be done to the top baffle

 

 

Sorry I can't help with your current problem, but in a previous nb, we had the exact same stove (with back boiler) and it worked a treat. It ran two rad's via a gravity system.

 

The 'furnace' was a bit on the small side and could only take a couple of logs at a time. It did, on the odd occasion, extinguish itself when you banked it in over night with coal. At someone's recommendation, we experimented with different types of coal. Again, not much use to you as I can't remember which one it was, but we did find a coal that was better suited to the fire than others.

 

It may be worth experimenting with coals or ask your supplier, he may be able to help.

 

Thanks for that. I'll have a word with the fuel supplier and see if there's another type of coal he can recommend. I'm currently using 'barge nuts' (really!) - a kind of small bore anthracite, I think

[bottle]

Have not read any of this but it may help, it has a technical section and brochure download etc.

 

http://www.stovax.com/products.htm?cid=4&sid=8

[Marc Harris]

Thanks. The boiler itself was 130 plus 280 for pipes and stuff and 100 to the fitter. Possibly over the odds but it was the cheapest quote so I went with it.

 

I'll investigate whether there is a an adaptation that can be done to the top baffle

 

I was thinking more along the lines of cutting it down at the back about the depth of the boiler to allow it to sit back where it was.... 5 minute job with an angle grinder

[far fetched]

Thanks Marc, I'll give it a go. I'm just not sure if the smoke can still esape safely.

 

If it doesn't work I might just keep going - fit wheels and a motor and enter it into 'Scrapheap'....

 

 

I was thinking more along the lines of cutting it down at the back about the depth of the boiler to allow it to sit back where it was.... 5 minute job with an angle grinder

[Smelly]

I had exactly the same problem, I just slotted the throat plate, a.k.a top baffle into the top of the fire and it sorted it nicely. The plate doesn't quite sit true but just sits on top of the boiler. Also with my Brunel 1 I had to remove the cowling and airwash vent as it got in the way. (That was the day I discovered my inverter would no longer run my grinder and by that time I was committed so off it came.)

 

The fire still easily stays in overnight burning Taybrite despite the airwash vent being wide open.

[blackrose]

Can you clarify this for me - how does the Brunel convert from non-backboiler to backboiler exactly?

 

I'm used to Morso stoves, which if I'm correct are either bought with a backboiler fitted or not. I wasn't aware that any stoves were designed to be converted. If the Brunel is, then why don't you get on to the manufacturers technical dept to ask them why it's not as good as it used to be?

Edited November 17, 2008 by blackrose

[Chris Pink]

I'm used to Morso stoves, which if I'm correct are either bought with a backboiler fitted or not.

 

Not so. The Squirrel can be retro-fitted, the boiler in that instance replaces the baffle plate and is fitted by removing the top of the stove so might not be easy in an old stove.

Edited November 17, 2008 by Chris Pink

[Proper Job]

Can you clarify this for me - how does the Brunel convert from non-backboiler to backboiler exactly?

 

I'm used to Morso stoves, which if I'm correct are either bought with a backboiler fitted or not. I wasn't aware that any stoves were designed to be converted. If the Brunel is, then why don't you get on to the manufacturers technical dept to ask them why it's not as good as it used to be?

Stovax offer a conversion kit for the Brunel (and probably their other stoves). You can get them to fit it, but have to get the stove out and send it to them. Alternatively, they offer a DIY kit for you to be able to do it in situ.

 

Our old boat had a Brunel with a back boiler when we got it. I also know someone who did a DIY converstion on one of these stoves and it worked very well.

[blackrose]

Not so. The Squirrel can be retro-fitted, the boiler in that instance replaces the baffle plate and is fitted by removing the top of the stove so might not be easy in an old stove.

 

Ah, my Morso Panther can't be retro-fitted like that.

 

How do you get the pipes from the back boiler through the back of a Squirrel if you're retro-fitting?

[bottle]

Knockouts I believe.

[wonderdust]

Ah, my Morso Panther can't be retro-fitted like that.

 

How do you get the pipes from the back boiler through the back of a Squirrel if you're retro-fitting?

 

I think i read somewhere that there are dimples cast in which are where you cut the holes.

[alan_fincher]

Knockouts I believe.

Certainly how the Villager stoves seem to be done, although it must take some nerve to try punching them out of cast iron without breaking anything else.

[Pete of Ebor]

I'm no expert [...and I don't actually have a boat... yet.. though me and the Lottery are wroking on it... weekly...] but I have been looking at and reading up about installing a stove in my house. According to the Stovax specs, the 1A has an output of about 4kW, but the website seems to suggest that in the boiler version, the boiler version will take 2kW of this, leaving you with only 2kW worth of room heating direct from the stove, and 2kW to the rads & water - that's if I'm understanding the specs correctly. 2kW does not seem much to run 3 rads and heat water.. wheras the full 4kW [without the boiler] is probably more that enough for space heating.. hence your describing it as a raging monster.. Sorry to say it sounds to me like it might be not quite up to the job..

 

sitting quietly waiting for the incoming...

[Proper Job]

I'm no expert [...and I don't actually have a boat... yet.. though me and the Lottery are wroking on it... weekly...] but I have been looking at and reading up about installing a stove in my house. According to the Stovax specs, the 1A has an output of about 4kW, but the website seems to suggest that in the boiler version, the boiler version will take 2kW of this, leaving you with only 2kW worth of room heating direct from the stove, and 2kW to the rads & water - that's if I'm understanding the specs correctly. 2kW does not seem much to run 3 rads and heat water.. wheras the full 4kW [without the boiler] is probably more that enough for space heating.. hence your describing it as a raging monster.. Sorry to say it sounds to me like it might be not quite up to the job..

 

sitting quietly waiting for the incoming...

The output of the stove is still the same = 4kW

 

Its just that 2 kW is emitted directly by the stove and the other 2kW you can re-direct to elsewhere in the boat (rads). There-bye evening out the heat distribution.

[Smelly]

I'm no expert [...and I don't actually have a boat... yet.. though me and the Lottery are wroking on it... weekly...] but I have been looking at and reading up about installing a stove in my house. According to the Stovax specs, the 1A has an output of about 4kW, but the website seems to suggest that in the boiler version, the boiler version will take 2kW of this, leaving you with only 2kW worth of room heating direct from the stove, and 2kW to the rads & water - that's if I'm understanding the specs correctly. 2kW does not seem much to run 3 rads and heat water.. wheras the full 4kW [without the boiler] is probably more that enough for space heating.. hence your describing it as a raging monster.. Sorry to say it sounds to me like it might be not quite up to the job..

 

sitting quietly waiting for the incoming...

 

It works quite nicely for us with around 1.75Kw of rads spread over 2/3 the length of the boat and plumbed into the calorifier. It takes a lot longer to warm the boat through, but careful choice of timber when we light it or stoke it in the am, so as to take full effect of the ravening beasty effect, helps minimise the lag. With a couple of bits of railway sleeper or good dry pine on it the rads get hot inside 1/2 hour and by then it's time to get up and make another brew.

 

New thread about changing glass to be announced imminently though!

 

edit... its a 58 ft scouser, door vents so a bit drafty.

Edited November 19, 2008 by Smelly

[Pete of Ebor]

The output of the stove is still the same = 4kW

 

Its just that 2 kW is emitted directly by the stove and the other 2kW you can re-direct to elsewhere in the boat (rads). There-bye evening out the heat distribution.

 

Yes.. Sorry. I didn't word my reply too well, but that is what I was trying to get across. 4kW output wont change, it's just that you'll now only have 2kW space heating and 2kW spread over the rest of the boat and calorifier. In comparison, the 2kW now available for direct space heating may well seem to be noticably less than the 4kW your 'raging monster' used to put out.

 

Looking at it another way, the same heat you had in your living area is now being 'spread' over a larger area so you'll all get a bit, but a bit less..

[Smelly]

Yes.. Sorry. I didn't word my reply too well, but that is what I was trying to get across. 4kW output wont change, it's just that you'll now only have 2kW space heating and 2kW spread over the rest of the boat and calorifier. In comparison, the 2kW now available for direct space heating may well seem to be noticably less than the 4kW your 'raging monster' used to put out.

 

Looking at it another way, the same heat you had in your living area is now being 'spread' over a larger area so you'll all get a bit, but a bit less..

 

Now here's a trick... We've a kW worth of rads in the saloon, and when the balance valve on both is open the rad in the bedroom won't get hot; it's gravity fed and there's not enough pressure to push it that far, but 1/2 hour before bedtime close the balance valve on the rad furthest from the fire and the bedroom warms up and then it was all worthwhile... Only works properly when the fire's roaring but that's when the bedroom needs it most.

 

The bedroom's got a bathroom and wardrobe between it and the fire and the heat struggles to get round the corner so the rad's all the more worthwhile.

 

I do wonder whether, as fires come with safety measures (for instance our brunel had a tab that prevented you opening the bottom door when the big door above was closed) the actual output, sans safety tab, is a lot more. It certainly feels that way.

 

Oh, and don't forget Pete, at least on a nb it's quite a small space you're heating. Granted it's not properly cold yet, but I've spent most of the evening taming the fire to help the boat cool down.

[bottle]

Smelly

 

Not trying to teach you to suck eggs and if you are happy the way your system works carry on.

 

If you would like both rads to work at the same time you need to balance the system, assuming the rads are piped in parallel.

 

The first rad 'balance' valve, the one with the plain cover if fitted, only needs to be opened ¼ to ½ a turn. (this may need to be adjusted either way to make it work).

 

The on/off valve should be fully open.

 

Water takes the least difficult path so restricting the flow into the first rad will force it to flow to the second.

[Smelly]

Smelly

 

Not trying to teach you to suck eggs and if you are happy the way your system works carry on.

 

If you would like both rads to work at the same time you need to balance the system, assuming the rads are piped in parallel.

 

The first rad 'balance' valve, the one with the plain cover if fitted, only needs to be opened ¼ to ½ a turn. (this may need to be adjusted either way to make it work).

 

The on/off valve should be fully open.

 

Water takes the least difficult path so restricting the flow into the first rad will force it to flow to the second.

 

"Balance" was the wrong way to describe the valve methinks. Being gravity fed I reckoned having a valve on the intake would seriously decrease the water getting into the rad; possibly more than in a pumped system as it's more prone to friction losses (guesswork admittedly), so there's only one valve on each, on the outflow. One is balanced so that some hot water gets up the boat,it makes it as far as the bathroom, but unless the second is shut it doesn't get up to the bedroom. One problem on my system is that there's a rise on the return from the bows/bedroom, so it takes quite a push to get it round. I do plan to resolve that next year before finishing the bathroom though.

 

The rads are tee'd out of the fire, in series on the inflow but in parallel on the out, in the middle of the system. It will all flow saloonwards with the outflow valves fully open due to the rise on the other side of the system. As an aside, it was a lined hull so hiding pipes behind the panels, which conveniently are glued to the battens, was not feasible.

[bottle]

Now totally confused on how you have plumbed the rads etc.

[Bagpuss]

Now totally confused on how you have plumbed the rads etc.

 

posing as SWMBO...

 

The fire's in the middle of the system. The saloon's sternward. Running toward the stern there are two rads; the feed from the boiler runs straight into the top of the 1st rad, then on the opposite side another pipe runs directly to the next. At the bottom they both drain, via valves, to a common drain pipe.

 

On the other side it's all parallel with no valves. In a misguided moment I thought finrads were a good idea so it's calorifier, then 1 twin finrad in the bathroom and two in the bedroom, all parallel. In the fullness of time the bathroom rad will get swapped for a towel rail and the bedroom rads will get boxed in.

 

Does that help?

 

Guidance is welcome, but as it stands it works, but could probably work better.

[bottle]

posing as SWMBO...

 

The fire's in the middle of the system. The saloon's sternward. Running toward the stern there are two rads; the feed from the boiler runs straight into the top of the 1st rad, then on the opposite side another pipe runs directly to the next. At the bottom they both drain, via valves, to a common drain pipe.

I assume by common drain pipe, this is the return pipe to the boiler(fire), the first rads valve wiil need to turned off for heat to get to the second rad as otherwise the water flow will take the shortcut back to the boiler (fire). Hence the second rad not getting hot until this valve is turned off.

 

On the other side it's all parallel with no valves. In a misguided moment I thought finrads were a good idea so it's calorifier, then 1 twin finrad in the bathroom and two in the bedroom, all parallel. In the fullness of time the bathroom rad will get swapped for a towel rail and the bedroom rads will get boxed in.

Without valves you will not be able to 'balance' the system or isolate a rad if you need to for example it starts to leak.

 

Does that help?

Yes and I thankyou for the explanation. I have now reached my knowledge barrier (not a plumber) so will bow out.

 

Guidance is welcome, but as it stands it works, but could probably work better.

Probably it can, let us hope someone can advise you better than me. (not difficult)

 

Good luck.