Back boilers....good or not?

guideanna

Hi All,

Just met with the plumber the other day to go through the details of the house i'm building.
It's a 1.5 storey, and i had been hoping to get a stove fitted int he main room with a back boiler to heat a few rads and/or the water.
Plumber from day one has been set against us getting a back boiler, thinks they are useless, says the only warm up the rads, don't heat them and same fr water. He says it takes a lot of the heat from the fire itself and we'd be better off without it.

I really thought it'd be a good idea to have the back boiler, even if only to heat a few rads in the downstairs rooms we'd be using (kitchen, sitting room, hall).
I'm just looking for feed back from any of you who have them and think they are good or not, or anyone who was going to get one and decided against it and if they think it was the right decision now!

Thanks!!

mr_edge_to_you

it's not an issue for us with our own build. we are just putting in an ordinary stove in sitting room. going with ufh and geo-thermal.

my parents recently installed (retro fit) a Waterford Stanley stove with a back boiler to heat some radiators and hot water. They are delighted with the results. But it does need to be lit for a fairly long period of time to generate real heat. It merely compliments their oil central heating, it doesn't replace the need for it! I understand that you also need to burn coal to generate higher temperatures, however I am open to correction on that. It makes sense in so far as you have a "fire" going and you are getting heat in your radiators as well as the room in which the stove is. In my opinion its a 2 birds, 1 stone argument.

The units with a back boiler do cost a fair bit more but in the greater scheme of things its not too much really.

JuniorB

I'm in similar situation. Was all set for the back boiler route but have been put off it in the end. ... mainly by guys in the stove places and the impossibility of getting a room sealed stove with external air supply and a back boiler.
The theory I've been told is that the back boiler will take the heat first and then the room will get the remainded. The 2 birds one stone was my way of thinking first off but I'm told it's more like 2 birds 2 stones ... you will need twice the fire to heat the water and heat the room so you are not really gaining anything.
I guess it depends when you will use the stove too. Ours will be more aestetic and will get a blast most evenings during the winter.
I'm looking at maybe running a few vents off the stove to directly pump a bit of hot air into some of the bedrooms just upstairs (either side of the chimney breast).... the idea being why heat water to heat radiators to heat the rooms when you can 'pump' the warm air in directly. Most seem to come with these vent systems now. Need to investigate a bit more .. could be some hygiene and health concerns. I've been put off the back boiler anyway. Best of luck which ever system you choose

mossfort

JuniorB wrote: »

I'm in similar situation. Was all set for the back boiler route but have been put off it in the end. ... mainly by guys in the stove places and the impossibility of getting a room sealed stove with external air supply and a back boiler.
The theory I've been told is that the back boiler will take the heat first and then the room will get the remainded. The 2 birds one stone was my way of thinking first off but I'm told it's more like 2 birds 2 stones ... you will need twice the fire to heat the water and heat the room so you are not really gaining anything.
I guess it depends when you will use the stove too. Ours will be more aestetic and will get a blast most evenings during the winter.
I'm looking at maybe running a few vents off the stove to directly pump a bit of hot air into some of the bedrooms just upstairs (either side of the chimney breast).... the idea being why heat water to heat radiators to heat the rooms when you can 'pump' the warm air in directly. Most seem to come with these vent systems now. Need to investigate a bit more .. could be some hygiene and health concerns. I've been put off the back boiler anyway. Best of luck which ever system you choose [/qu


what sort of vents can you put on a stove to pump hot air into other rooms??

JuniorB

I'm no expert Mossfort but a lot of the stoves I've looked at have this feature... secondary hot air outlet.

I've attached a diagram that might explain it better..

Poor Uncle Tom

A few things come into play in the use of a back boiler, imo.

I think a fire needs to be constantly in use, not just lit now and again, for a back boiler to be of maximum value. The hot water tank needs to be very close to the back boiler (mine is less than 2.5m away) and needs to be very well insulated. This means the water going to the rads is hot, not just warm. The amount of rads in the circulation system need to be calculated well and not overdone as a small circulation system will reach and stay at optimum temprature faster and therefore work more efficiently.

This should not be the primary or only means of heating a home. It can be a secondary or subsidiary means only.

bbam

Hi..
In our last house (2600 sq ft bungalow) we had a Grant triple pass back boiler in the living room, with a good fire the rads were warm in an hour and real hot in about 2.5 hours, when the fire wasn't in use the oil would heat the back boiler and some heat was definitely lost, we lived there for 12 years and overall loved the back boiler..

In our current 1.5 story 2800 sq ft house we have a hurcules stove with 100K BTU boiler... mad yoke altogether we usually have to let the fire die down after two burns as the house is about 25degrees.. It is in a 15*30 room and anything smaller would be uncomfortable as it is we need to keep hall door open to let heat out..

A stove is a better option from room sealed perspective when not in use, new plumbing means boiler in stove doesn't heat up when only the oil is on..

The only compromise we had to make is that the upstairs zone is plumbed with a bypass of the valve to be at least 50% on at all times to disapate heat from the stove safely.

Cheers

mossfort

JuniorB wrote: »

I'm no expert Mossfort but a lot of the stoves I've looked at have this feature... secondary hot air outlet.

I've attached a diagram that might explain it better..

it seems you would need to have the stove in a sealed enclosure .
those two pipes wouldnt carry a lot of heat to the upstairs room id imagine.
the only way of knowing would be to see it in use.

guideanna

Thank all for the feedback.
Spoke with the engineer today also who agreed that the backboiler idea is often better than the reality of it. He said the backboiler will only "warm" the rads and you wouln't rely on it to heat the rooms and it also takes a lot from the stove heat so i think we're going to get the pipes fitted for it but not get it all connected and at least it's there if we want it in the future.
I must ask the plumber about what JuniorB was talking about. Our kitchen is on the otherside of the fireplace wall and a vent carrying some of the heat in there would be brilliant, but i'm not sure how that would work with smoke issues etc.

RKQ

guideanna wrote: »

Our kitchen is on the otherside of the fireplace wall and a vent carrying some of the heat in there would be brilliant, but i'm not sure how that would work with smoke issues etc.

The hot air accumalates in an insulated box above the stove, this heat is piped to other rooms so there is no smoke issues. I've seen these pipes at stove shops & shows etc. I recommend you visit a "happy customer" with it installed to see for yourself.

A kitchen with living room on other side of wall - did you consider a double sided stove? Expensive but very attractive.

I would definately install the pipework for a back boiler, much cheaper to do now rather than later.

castlemoy

hi
can you heat more than one zone in a house off a stove???

kdouglas

Just moved into our first house and there was a back boiler installed already.

The previous owners said that it only ever really got the radiators warm for them, but we gave it a good clean and with a decent fire going for about an hour or so, we turn on the pump and the downstairs radiators get piping hot in about 60 seconds.

When using the fire, we generally keep the backboiler flue closed for the first while, until the room is heated and the fire is going properly, then open it so that the backboiler gets a good bit of heat from the fire, this does make the amount of heat coming off the fire noticeably less, but at that stage the room is hot already so it doesnt make much of a difference.

guideanna

RKQ wrote: »

The hot air accumalates in an insulated box above the stove, this heat is piped to other rooms so there is no smoke issues. I've seen these pipes at stove shops & shows etc. I recommend you visit a "happy customer" with it installed to see for yourself.

A kitchen with living room on other side of wall - did you consider a double sided stove? Expensive but very attractive.

I would definately install the pipework for a back boiler, much cheaper to do now rather than later.

I've heard these can cause a lot of heat loss, and tbh if they are a lot more expensive we wouldn't be able to afford it, we've already been told by the engineer that new laws brought in mean we "must" have a source of renewable energy so we now have to get solar panels will we'll be looking at around 5k for. More expense we hadn't planned on...

guideanna

kdouglas wrote: »

Just moved into our first house and there was a back boiler installed already.

The previous owners said that it only ever really got the radiators warm for them, but we gave it a good clean and with a decent fire going for about an hour or so, we turn on the pump and the downstairs radiators get piping hot in about 60 seconds.

When using the fire, we generally keep the backboiler flue closed for the first while, until the room is heated and the fire is going properly, then open it so that the backboiler gets a good bit of heat from the fire, this does make the amount of heat coming off the fire noticeably less, but at that stage the room is hot already so it doesnt make much of a difference.

Thanks for that, sounds like a good way to run it alright.

volvo 240

We have a <SNIP> woodburner with 45,000btu wraparound integral boiler that is great at heating our 11 radiators with a combined output of 11.6kw. Bought new in the UK for 780 pounds.
We got rid of the 12 months old oil boiler as it used to cost 1400euros to heat our 100 sqm old stone Normandy home. Kitchen, entrance hall, wc, study, entrance hall, living room, 3 bedrooms and bathroom. The weather here is very cold with daytime temps around freezing and nightime temps of -7. Our stove just burning wood gets the rest of the house up to 21-22 degrees. Coal here is very expensive at around 18 euros for a 25kg bag so we don't buy it. We buy 20 cubic metres of wood for 650 euros pre cut and delivered. The stove stays in overnight on 3 large logs and is simply the best thing to look at rather than a radiator!! We are going to install a <SNIP> in our new place in Kerry with bacboiler!! I can't fault it for its performance!! James.:)

Edit: Names by PM only please.

Deregos

Is anyone aware if there's a stove available that can be linked directly into the nearest rad pipes, so that it wouldn't require me ripping apart half the house. The fireplace is positioned a good distance away from from the emersion which is upstairs & to the back of the house.
A bloke in the pub told me its possible but my mate says hes a big spoofer.;)

bbam

Deregos wrote: »

Is anyone aware if there's a stove available that can be linked directly into the nearest rad pipes, so that it wouldn't require me ripping apart half the house. The fireplace is positioned a good distance away from from the emersion which is upstairs & to the back of the house.
A bloke in the pub told me its possible but my mate says hes a big spoofer.;)

That would be a big no no, the bore of the heating pipes to a rad wouldn't be fit for the job, it either just wouldn't work or would boil the water constantly risking a rupture and nasty accident.
If your doing it, do it right..

No6

They need to be connected to a cylinder. We are going to reto fit a stove with a back boiler into our sitting room. We have oil and woodpellet heating systems but anytime I am away they breakdown and the misses can't get them going again so we've decide to go for something she can work, fire, she usually has huge blazes going in the stove we have anyway so the leap to one with a back boiler shouldn't be huge, all we need now is the plumber to finish fixing leaks and do the damn thing!!

Jazzanne

I should like to know what people think is the best back boiler for an open fire.

Poor Uncle Tom

Not by resurrecting a zombie.........