How not to ruin heating?

[a84]

Hello,

I have a 140 m 2 house in Avignon, not isolated at all (except the roof: 5 cm!), With large stone walls of 55 cm and ceiling height of 305 cm. The openings are single glazed. The house is on four levels (ground floor, 2 floors, attic space).

The icing on the cake: the boiler. An old wood boiler converted into a fuel boiler (with, however, an excellent burner: weishaupt). I'm not telling you the efficiency ... Large cast iron radiators recently fitted with thermostatic valves.

Ecologically and economically, my house is a disaster: between 2000 euros and 3000 euros of fuel oil per year and Hymalayesque gas emissions (the thermal diagnosis at the time of purchase classified the house in category "G"). What also to say about the openings which, on mistral days (ah! If I had known about this f ... mistral, I would have looked twice before living in Avignon), let through m3 of icy air .


Last useful clarification, there are five of us at home (3 children) and I am the only one to work (because 2 little twin binoculars arrived two years ago!), 3500 euros monthly, CIF included.


So I have a crucial problem: to save on heating costs without investing too much.

I thought in all directions:

1. Insulation from the outside: on its east and north facades my house overlooks the public domain. So niet.
2. Insulation from the inside: quite complex to achieve for this house but above all the problem of the choice of material. Mineral wools are on paper the most efficient but I read everywhere that it is not suitable for stone walls (pb of breathing, condensation). But when I see the price of green insulation, I give up. Result: the insulation work has not progressed.
Specific case of roof spaces: they are habitable, so I have a problem of height under ceiling: apart from the insulation by the outside, I do not see other solutions.
3. Heating. I quickly dismissed the heat pumps, because my installation would require a high temperature heat pump, therefore very energy-consuming (in PS, I will deliver the misadventures of 2 friends recently passed by the heat pump). For wood, I thought of pellet, but I don't have room in my boiler room to install the silo; as for the log chore, no way. I thought for a while to install an oil burner on my boiler, but impossible to find sufficient recovery oil, let alone maintenance. There remains the gas, for which I made quotes ... startling: between 7 and 1000 euros.
4. Windows: the quotes I made all revolve around 1000 euros per opening (my windows are almost all the size 210 * 100).


This is where I am going to piss off more than one: I have the feeling that saving energy is a luxury reserved for a minority. My problem - I hope you understood it - is above all a problem of under:
at. if i have to put 1000 euros in a window (half or a third of my fuel bill), how long will it take to recoup my costs? 25 years, 30 years? I may have sold the house by then ...
b. If I have to put 7000 euros (ie between 3 and 5 years of fuel bill) in a tip top condensing boiler, how long will it take to recoup my costs?

I come to my current positions and I deliver them to you for your opinion:

. I postpone the insulation of the walls
. I plan to change the windows myself through the Lapeyre "Easy Renovation" where the old buildings are preserved.
. I am looking for a recent second-hand gas boiler with maintenance contracts; I found a retired heating engineer who installed it in black for about 500-1000 euros (you must also remove the old boiler which is titanic).

More philosophically, do you think it is right to place on ordinary people the full weight (financial and moral) of the choices made since the beginnings of the industrial revolution and the consumer society?


Thanking you for your informed answers.

PS:
1st friend: large house of 250 m2; dilapidated fuel boiler; cast iron radiator; replacement with high temperature PAc (13 euros). Result: 000 euros of electricity between October and January. His wife wants to divorce + lawsuit to the installer.
2nd friend: same type of house a little better insulated; Low temperature heat pump for 14 euros. I spend a mistral day at his house; the cap was picking up, result: oil stove in the living room. I was hilarious.

[dedeleco]

Some reactions:
change the absurd and expensive windows for a very small gain on a house without insulation.
Avignon is not cold.
The thick walls insulate not bad.
The mistral forces to reduce leaks by caulking the windows with strips glued in the window edges, or even to condemn part of the windows, to better block excessive leaks.
It is necessary to better insulate the attic or roof yourself for cheap, except the installation work.
In my opinion the bill should drop sharply, by half, by caulking the window sills with adequate rubber bands !!

Finally without money, I would put the wood boiler back, coming from the plant recycling center, where we all give up pruning and hedge trimming which only require burning quickly dried with the mistral. !
For cheap you have to agree to do the work of putting cheap wood there and to sweep often!
The boiler can easily increase its real output by decreasing its maximum power and its regulation to decrease the rate of starting and stopping !!
Measure the temperature of the gases leaving the chimney in continuous operation, it determines the efficiency, it must not exceed 130 to 150 ° C, otherwise these hot gases take all the heat outside !!!
By decreasing the power of the boiler to have this temperature, we increase the efficiency, heating just as well, since the excess heat goes directly into the chimney !!!!
This avoids changing the boiler by simply adjusting it better !!
We can gain a factor of 2, if no luck at the start, on a powerful boiler, but with an undersized exchanger, in the case of old boilers. !!!
The case happened to me with a gas boiler of this kind 30 years ago, reducing the gas valve to half doubled the performance !!
After such a common sense setting, changing the boiler will only save 20%.

Be wary of many professionals who aim to pump the maximum amount of money, taking advantage of the lack of competence of clients.
drafts change windows while old-style caulking costs almost nothing.
deplorable efficiency boiler to change when it suffices to halve the combustion speed !!

Insulate from the outside 200 € per m2, except do it yourself.

There are fully automatic burning wood boilers, close to € 20000, but effective because all the small wood thrown out of a crusher burns automatically.


Finally, the poorest are rolled over than the rich, and it is unfair, difficult to change, even with revolutions that give dictators.

These old houses with thick walls were not heated in winter before 1930, but had the temperature of the soil which rose through the walls, 10 to 15 ° C (without leaks from the caulked windows) and people, as in castles, slept with lots of pajamas, caps and hot water bottles !! The old fireplaces heated almost nothing, true even for the Palace of Versailles.

[dedeleco]

Finally, the large boiler must be insulated with glass wool around it to reduce losses unless it heats a room !!
Also try to make sure that it starts very rarely, because you lose a lot in heating the whole boiler.
For that put a tampered thermostat to have a great hysteresis between the high temperature (which stops) and low (which starts) of several degrees !!

Finally if you put the gas boiler, I would keep as much as possible the big boiler by putting it on wood, if necessary, in case the price of gas explodes.

[a84]

Thank you for your response ... substantial. I have already caulked the windows with a silicone seal: we have gained much in comfort, difficult to quantify the savings ...

I do not understand this part of your message: "We can gain a factor of 2, if no luck at the start, on a powerful boiler, but with undersized heat exchanger, case of old boilers. !!!"
Maybe it's because it's late ...

[a84]

I forgot: you are talking about putting wood in the boiler. On the said boiler, I have the burner at the bottom of the heating body, and 50 cm above a sort of hatch which opens onto the interior of the heating body. Does this mean that I can put the wood directly through this hatch. How to dispose of the ashes?

[bobono]

I say pellet stove or possibly pellet burner.

Of course it is wrong that fuel is available in your area.

[dirk pitt]

I understand very well your position for having experienced something similar.
my choice fell on a granulated boiler + complete interior insulation before entering the premises. I know it's harder to do after the fact. when the place for the silo, I did not have it either, I made an apprentice of 5m2 against the wall of the house.
the pellet solution is expensive, even more now than when I did it because there were then large subsidies.
it still seems valid to me in the long term.
on the other hand I do not believe too much in the interest of changing for gas. the delta will be low compared to the price of the installation.

the solution at lower cost that I would suggest would be to replace your old "wood modified fuel oil" boiler with a recent second-hand fuel oil boiler, keeping your burner (preferably cast iron heating body). indeed the efficiency of the heating body of an old transformed wood boiler is absolutely lousy! in addition, there is a good chance that it is oversized. do not take a 50kw boiler if half is enough. the larger the boiler, the more losses it has. it is better to have a lower power boiler which operates for a long time than a very powerful boiler which stops after 3 minutes of operation.
a boiler that operates less than 1000 hours per heating season is considered to be very oversized, the average being between 1500 and 2000 hours of operation.
if your current burner has an intake shutter during shutdown phases, keep it, otherwise sell it and buy one that has this function. it is very effective in avoiding losses by sweeping air from the boiler.
the graph below shows that the more often the boiler works (load factor) the more the output approaches its maximum.
we see that this is all the more true when the standstill losses are large (hence the suggestion for the shutter burner)
with an old boiler whose standstill losses are large and moreover oversized, you accumulate the losses.

second, and not important: invests for very little money in efficient regulation: three-way pilot valve and external probe. it really makes a difference. it has nothing to do with thermostats on radiators. little explanation:
the heating efficiency will be lower the higher the water temperature of the radiators. this is due to losses in the boiler and pipes.
it is therefore useless to heat water to 70 ° which we send in all the pipes so that once arrived at the radiators, the thermostats take only a small part because they are half closed .
the performance is optimal when the radiators are wide open and the water which arrives there at the temperature "just" necessary but not more. it is the role of the regulator which calculates the temperature of the water according to the difference of t ° int / ext.
I assure you that this makes huge savings especially if you set it up correctly and play comfort and reduced hours.
if you can, also insulate the pipes that pass in unheated areas.
with a house with several floors, the ideal would also be to have separate circuits by floor but if that is not planned, difficult to modify. to watch anyway because according to the implantation, a more well placed pipe that descends to the basement and it also allows it to better manage the natural tendency of heat to rise.
I did not talk about insulation: I am less specialist but obviously, everything you can do at a lower cost in this area, especially in the attic will be effective.

[bernardd]

If this house is located in Avignon, it is worth investing in solar thermal energy rather than changing the boiler or putting in insulation, given the small number of cold days and the amount of sun in winter.

[dirk pitt]

If this house is located in Avignon, it is worth investing in solar thermal energy rather than changing the boiler or putting in insulation, given the small number of cold days and the amount of sun in winter.

a84 is looking for a lower cost solution.
thermal solar will not be in this niche.
in addition, heating by radiators (existing) with thermal solar ??? not adapted.
redo heated floors under renovation? almost impossible especially on a two-story house.

[bernardd]

a84 is looking for a lower cost solution.
thermal solar will not be in this niche.
in addition, heating by radiators (existing) with thermal solar ??? not adapted.

You're a bit dated ... It's been a long time since solar thermal collectors have been raising water between 60 ° C and 80 ° C without any problem, especially in Avignon, even in winter.

when the price, look at the price of the sensors compared to the price of fuel or insulation, which is in any case useless in Avignon with how many cold and not sunny days per year?

http://www.bysun.fr/__Capteur_Solaire_A ... t_146.html

ou

http://www.bricodepot.fr/avignon/chauff ... au-solaire

And they are accessible by DIY, especially if installed on the terrace. We can install them gradually to see the interest in situ: more hot water costs, and in Avignon, more heating costs ...