Thermal store + wood-burner (HELP)

[Chris J]

Morning Guys,

I'm looking to install a word-burner / central heating with thermal store as our only heating system (don't have any other cost effected options). Finding it very hard going getting reliable info on such a system, just wondering if anyone has been down this road and could share their knowledge.

Or if anyone has any good web-links on this type of set-up that would also help as I'm just going around in cycles, when I think I have a understanding I read something else and I'm at a loss again.

Oh the good life less stress

 

[ianmcd]

if I read your post correctly , you are asking if you can use a wood-burner as the heat source for a thermal store? do you really mean a thermal store ? do you know what a thermal store is ?

 

[Chris J]

if I read your post correctly , you are asking if you can use a wood-burner as the heat source for a thermal store? do you really mean a thermal store ? do you know what a thermal store is ?

I'm at a loss has to why you have posted such a unhelpful reply....

A quick google gave me this:

A thermal store is a way of storing and managing renewable heat until it is needed. In a domestic setting, heated water is usually stored in a large well-insulated cylinder often called a buffer or accumulator tank.

CJ

 

[ianmcd]

yes but the "thermal store" has to be controlled in order to stop it over heating, how are you going to do that with a wood burner? suppose it could be done but would need a lot of design and external controls and heat dumps , not as straight forward as you might think

 

[Chris J]

yes but the "thermal store" has to be controlled in order to stop it over heating, how are you going to do that with a wood burner? suppose it could be done but would need a lot of design and external controls and heat dumps , not as straight forward as you might think

Yes this is the reasoning I'm here asking if anyone has been down this road and willing to share their knowledge!

 

[Doggit]

There are a couple of guys on here that have done that sort of thing (Burnerman and Firebrand) and with a bit of luck, they'll turn up soon.

The problem with using a wood burning stove, is that you have little control over the heat output, and little feedback for the thermal store (hot water tank may be a better description) or the central heating to stop the logs from burning.

 

[ianmcd]

@Doggit a thermal store and a hot water tank are two completely different animals , one is the complete opposite of the other

 

[Doggit]

Yes, but I'm working on the assumption that he needs hot water as well as central heating. But good point; Chris, how are you anticipating using the thermal store. Ians right in many ways. You can put heat into a thermal store for later use, and then use that to heat up a smaller hot water tank.

 

[Chris J]

Yes, but I'm working on the assumption that he needs hot water as well as central heating. But good point; Chris, how are you anticipating using the thermal store. Ians right in many ways. You can put heat into a thermal store for later use, and then use that to heat up a smaller hot water tank.

I'm looking (hoping) the store will supply mains pressure hot water from one of the coils- if my understanding is correct.

CJ

 

[Doggit]

In theory it should ( I know the principles) but I'd say it isn't the best way to go. You need a much larger thermal store to heat the hot water, than you would just having a hot water tank. But what are you intending to do when the wood burning stove isn't on. With a hot water tank, you can have an immersion heat in it (not the best option) for the summer months, and it can be on an a cheaper overnight rate to heat the tank. The thermal store also works well with solar, in that you get the store heated in the summer, and the stove heats it in the winter.

What is your overall scenario.

 

[bernardgreen]

Have you tried the Centre for Alternative Technology.. They used to give a lot of free advice based on living with and depending on alternative technology. Even though they have grown out of their hippy happy youthful beginnings and become middle aged and commercial they still have sound ideas about proven alternative energy systems.

https://content.cat.org.uk/index.php/biomass-consultancy

 

[Chris J]

Morning Guys,
Thanks for the input so far:

So folks know where I'm coming from with this, the house is rural and isolated no gas - electric is unreliable oil far to expensive, wood is the only real option. Gas/oil would be so much easier.

Things I want to archive:

Winter Time:
Heating that stays warm over night so we don't wake to a cold house, hot water for showering in the morning.

Summer Time:
Hot water showering etc.


I have no fixed ideas so very open to suggestions, I just want to get it right first time of the bat.


Kind Regards
CJ

 

[Madrab]

The long and short of it is a thermal store needs a reliable heat source that can maintain the large volume of water at a specific temperature to reliably supply mains hot water and central heating. A wood burning stove can be used but to ensure the temperature is maintained in the store the wood burning stove would need to be on constantly and has a backup as a top up facility say via a immersion heater. That being said these systems usually always have a primary oil or gas heat source.

Using a solid fuel stove as a primary heat source could be adapted but you would need an experienced HETAS installer to design it properly. This type of system needs several safety systems including a heat soak, there is no other option if that is the primary heat source though I believe that's already been mentioned. There are a also lot of other safety systems attached to the store. BTW, this will not be a cheap system

This schematic will give an idea of how they are put together -

https://www.advanceappliances.co.uk...Multi Fuel Thermal Store Leaflet 16-01-17.pdf

 

[Doggit]

I had a quick look at that Madrab, and although it says "wood burner" I'm wondering if it means wood pellet, as they can be controlled. Very interesting solution though.

Chris, you haven't mentioned a budget, and you've said that oil is too expensive, then gas/oil would be easier. Have you look at LPG costs, and as the electric is unrelaible, what about a micro generation boiler that'll generate electricity while it's on.

A wood pellet burner would give you all the control you want, but not the electricity, so unless you're going to go green, with solar, and a wind turbine to back up the wood stove, I don't think you'll have everything covered properly.

 

[Chris J]

My thinking on the system:

Heat dump radiator in the loft space.

Pressure relief valve to the outside.

Header take to replace and loss to the system and dump for any over heated water.

Heat coil to supply hot water.

Some valve set-up to send all heated water when thermal store is at temperature to the radiators- this I hope will stop it boiling.


I'm probable barking up the wrong tree, but then that's why I'm here asking question.


I will take a look at pellet burner


Kind Regards
CJ