Boiler stove with gas combi boiler central heating and hot water 24 March 2022 at 2:03PM in Green & ethical MoneySaving 12 replies 201 views

M0ney

Hi all,

I'm hoping someone on here will have experience with something like this.

I have a very old house (c1782) with a conventional hot water and heating system, powered by a mains gas combi-boiler (no tank). There is also a multi-fuel stove in our kitchen/dining room which is in poor condition and as a consequence we don't use it much because most of the heat just goes up the chimney.

The plan is to replace the multifuel stove but since I am able to source a large quantity of wood for free (excluding the cost of fuel to transport it albeit minimal as I don't have to go far to collect it) I would like to source a multifuel stove with a boiler and at the same time install a water tank so that I can use this to heat the water, thus significantly reducing the amount of gas I use, I would also like to have the option to tie in a solar water heater into this tank if that is a possibility, this would obviously mean that I can still get free hot water in the summer when I am not going to have the fire on. I'm hoping to be able to have these two heating/hot water systems integrated seamlessly, so that the gas gives us the heat and hot water we need when the fire isn't providing it and the fire takes over when it's lit. 

So what I have done so far is that I have contacted a heating company to quote me to do this, unfortunately they are so busy they can't visit me to issue a quote until the end of May, in the meantime, I'm wanting to get a bit more clued up on what doing something like this would entail so that I can ask the most appropriate questions and not delay the install because I am sure that the lead time will be at least 3 months, possibly significantly more once I receive a quote and I really want to have this all ready to go for October, November at the very latest. 

In my previous home I did something a little like this but instead the fire was only connected to 4 radiators in the house and didn't provide and hot water as we had no tank and we had a gas boiler which gave us hot water and heat to the other radiators so the 2 systems were completely separate from each other.

I know that this is going to be expensive, I'm hoping that £7000 will cover it although I'm really not sure. I'd be really grateful for feedback from anyone who can share some useful knowledge about doing this.

Thanks in advance. 

Hexane

Looking at the solar side of it to begin with, and assuming (or asserting!) that solar PV is the way to go, not solar thermal, some things to check first:

1. is it a listed building?

2. is it in a conservation area?

3. what is the roof made of and is it in a good state of repair?

4. what size are the roof orientations that you might be able to fit solar panels to (directly south is best, east and west facing have advantages of their own, directly north-facing is no use)

5. what part of the country are you in?

a decent solar installation even without battery storage might eat up a large part of your £7000 budget on its own, with the way prices are at the moment. Still worth doing though...

QrizB

It's doable, but it's a relativerly complicated system.

I think you'll be able to keep your current boiler but I'm pretty sure you'll need to go back to a tanked water system.

I'm not in any position to judge whether £7k will cover it; Checkatrade think that the solar part alone will eat £3-6k.

M0ney

I should clarify the solar side of things would be something that I might do in the future, the £7k is for a tank, the boiler stove, and all the necessary items to go along with installing that. I've looked at solar PV and I was quoted more than £9k which I thought was ridiculous but I thought solar thermal might be a little more reasonable and I also thought that it might work quite well once I had a water tank installed in my house.

M0ney

Thanks a lot for your response....

Hexane said:

Looking at the solar side of it to begin with, and assuming (or asserting!) that solar PV is the way to go, not solar thermal, some things to check first:

1. is it a listed building?

Even though it's so old, I'm pretty sure it isn't

2. is it in a conservation area?

No

3. what is the roof made of and is it in a good state of repair?

The roof is slate and it's in reasonably good shape

4. what size are the roof orientations that you might be able to fit solar panels to (directly south is best, east and west facing have advantages of their own, directly north-facing is no use)

The front is almost directly south facing, the problem is that we are limited by a velux and 2 dormers, another reason why I considered solar thermal because they need a smaller footprint, don't they...?

5. what part of the country are you in?

I'm in the north-east, roughly half way between Aberdeen and Inverness.

a decent solar installation even without battery storage might eat up a large part of your £7000 budget on its own, with the way prices are at the moment. Still worth doing though...

I've had solar PV on a previous house, why is it so preferable over solar thermal?

Hexane said:

Looking at the solar side of it to begin with, and assuming (or asserting!) that solar PV is the way to go, not solar thermal, some things to check first:

1. is it a listed building?

2. is it in a conservation area?

3. what is the roof made of and is it in a good state of repair?

4. what size are the roof orientations that you might be able to fit solar panels to (directly south is best, east and west facing have advantages of their own, directly north-facing is no use)

5. what part of the country are you in?

a decent solar installation even without battery storage might eat up a large part of your £7000 budget on its own, with the way prices are at the moment. Still worth doing though...

M0ney

Is there nobody in our midst who is somewhat knowledgable about gas and solid fuel heating systems?

QrizB

M0ney said:

Is there nobody in our midst who is somewhat knowledgable about gas and solid fuel heating systems?

I'm not sure quite what you're hoping for.

You're doing something quite unusual and the chances of anyone else reading this thread having been through a similar installation is minimal.

To give a detailed analysis and assessment of your specific case would take far more work than I would expect any poster to put in. If you were to pay a pay a professional to analyse your needs and produce a detailed plan it could easily cost £500 or more, without a singler pipe or tap being changed.

M0ney

I'm not looking for a detailed assessment, just wanted to give my post of bump. The main thing I am interested to know is how easy it is to combine two distinct heating systems any maybe what components are involved, nothing specific. I'm not looking for someone to spend hours researching and compiling a report. Given that there are many people on this forum it doesn't seem that far fetched that someone with some knowledge in this area might see this thread and be able to point me in the right direction.

gefnew

Could be like having zoned system of some kind with various three port valves maybe. This may help with the research.
Central heating boiler stove | Stovesonline

paul991

may be some thing like this https://www.heatandplumb.com/acatalog/telford-thermal-store-open-vented-1850mm-450mm-combination-cylinder-with-solar-thermal-coil-and-sealed
using one  coil  for log burner one  for  gas and one  for solar thermal or  3 kw  immersion
maybe  you should  contact hetrae  sadia im sure they could  advise  you better

M0ney

Thanks a lot guys, this was very helpful.