To choose a new boiler, you must take account of the following factors:
- the type of fuel
- the efficiency
- the combustion system
- the space available in your home
- your hot water requirements
With regard to the price, you must take account of the purchase price but also the running costs. A more efficient boiler (for example a condensing boiler) will require a financial effort at the time of purchase, but this will be redeemed little by little every day during the initial years and will then start saving you money.
You should also take into account the Rénolution grants available for certain types of boilers, which make them more affordable.
Are you building? Before thinking about boilers, examine other alternatives: the “passive house” (ultra-low energy requirements), without heating or with cogeneration (simultaneous production of heat and electricity).
If you have to replace an existing boiler, look for independent advice at Homegrade, from an architect, from someone you know who has done the same thing recently etc. Then consult the manufacturers’ websites, compare installation estimates and enquire about the reputations of the installers. Also ask the heating specialist to justify the choice of model that he suggests.
These are the most important points to be taken into account when making your choice.
A highly efficient boiler will enable you to save on your energy costs and will reduce CO2 emissions. This is true of low temperature gas boilers (carrying the label HR+) and even more of condensation boilers (with the label HR Top). These models are more expensive but more economic to run. With regard to oil, the low-temperature and condensation models carry the labels Optimaz and Optimaz Elite.
There are two systems:
Low-temperature and condensation boilers come in two versions.
For your hot water, you can also choose between several solutions. Factor in your habits, the quantity of water you need (according to whether you generally take baths or showers, whether you live alone or not etc.).
When renovating, do not be satisfied with just replacing the old boiler with a model of equivalent power. The calculation methods of the past are no longer applicable. Have a heating specialist check the actual and present needs of your dwelling with regard to heating power. Take into account the improvements to it (insulation, double-glazing, proofing etc.) which have already been carried out or are planned.
Consider installing back-up heating (wood or pellet stove) to be used in between-season periods or as a supplement during very cold periods.
Calculations of the theoretically necessary power take account of certain weather conditions which last only a few days in the year. Do not then be too ambitious to too little effect and avoid over-powering the boiler. Otherwise, wasteful consumption is guaranteed! With regard to the cost, you also win: the prices increase faster than the power in the same range of boilers: a (very) powerful model will be proportionally more expensive than a less powerful one.
Have a check carried out to see if the chimney can take the presence of condensates (flow of slightly acid water coming from condensation). If not, there are some solutions: intubation, sealed boiler. Also, a low-temperature boiler needs bigger radiators to increase the heat exchange.
Have your heating specialist check that your existing radiators have a sufficiently large exchange surface. If they do not, it may perhaps be necessary to add one or two or to replace one or other of them.
The best of boiler will fail to give its best if it is not controlled by an efficient regulation system: a programmable thermostat, outdoor sensor and thermostatic valves add a certain value to your boiler: a form of “intelligence”…
New boiler: nothing but benefits!
A couple of weeks ago I had my boiler replaced and I haven’t yet regretted it for an instant. I am enjoying greater comfort and more safety... and I’m curious to see my first adjusted bill!
Sandrine and her husband have two children and live in Evere. They have just had their old central heating boiler replaced by a small condensing boiler which is more suited to the needs of the family. Sandrine gives the following account of it.
"We bought an apartment in an old single-family house. At first there was just one gas boiler for the whole house, but our neighbour soon had her own heating system installed in her flat. We didn’t have enough money for that, and for a while we made do with the old boiler.
But then the “safety” factor took priority. As we were expecting our second child and had just redecorated a number of bedrooms, we wanted a new boiler that didn’t pose any risk of carbon monoxide poisoning, for instance.
And now we’re on cloud nine! First and foremost, we have really saved space with the new boiler. It’s a very small wall boiler that doesn’t take up too much room in the utility room. And it makes far less noise! But what’s more, it’s measured on the basis of our real heating needs, which means that it is less powerful and uses less than the previous one. We also took the opportunity to have a room thermostat fitted.
I’m assuming that the adjusted bill next month will be a pleasant surprise!"
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