Hello
My wife and I are currently planning to build a one-and-a-half-story single-family house. We have already done extensive research, so we basically know quite well what we want ... and what we don't. The only question giving us some trouble is choosing the best heating system for us, especially because we find very conflicting opinions online on every aspect.
I will try to describe our starting point and what we would decide on based on our current knowledge. I hope there are some people here who can offer us advice and/or guidance.
By default, the house we have chosen is designed with a solar thermal system on the roof (for hot water) and a gas condensing boiler. What we have definitely decided on is underfloor heating (supply temperature 35°C (95°F)).
Last week, I had a consultation with the consumer advice center on this topic, and they recommended expanding the heating system to include an air-to-water heat pump and using the gas boiler as a backup for very cold days. So the air-source heat pump would run as long as outdoor temperatures are above freezing, and the gas boiler would heat when temperatures drop below 0°C (32°F), because the efficiency of an air-source heat pump decreases rapidly below freezing. For the transitional period, they also suggested a fireplace, which is not an issue since my wife wants one anyway.
In addition to the heating circuit described, we would like an automatic ventilation system with heat recovery. With our current knowledge, I would prefer the decentralized version. On the one hand, the initial investment is lower than with a central system (and very likely also the maintenance costs), and on the other hand, my uncle has a similar system in his house and has never reported any negative experiences.
I don't have the exact roof dimensions at hand right now, but the house has external measurements of 9m x 10m (30 ft x 33 ft) and a 45° pitched roof. By rough calculation, one half of the roof offers about 65m² (700 ft²) of space. We have been considering whether it makes sense to use only about two-thirds of that area for solar thermal and the rest for photovoltaic panels. This way, we could produce some of the electricity needed by the air-source heat pump ourselves.
That’s all I can think of for now.
We appreciate any advice, as I’m quite sure we have simply overlooked some points in our considerations so far. Also, I assume there are users here who know more about this than we do and have considerably more practical experience.
Best regards from the very sunny North!
My wife and I are currently planning to build a one-and-a-half-story single-family house. We have already done extensive research, so we basically know quite well what we want ... and what we don't. The only question giving us some trouble is choosing the best heating system for us, especially because we find very conflicting opinions online on every aspect.
I will try to describe our starting point and what we would decide on based on our current knowledge. I hope there are some people here who can offer us advice and/or guidance.
By default, the house we have chosen is designed with a solar thermal system on the roof (for hot water) and a gas condensing boiler. What we have definitely decided on is underfloor heating (supply temperature 35°C (95°F)).
Last week, I had a consultation with the consumer advice center on this topic, and they recommended expanding the heating system to include an air-to-water heat pump and using the gas boiler as a backup for very cold days. So the air-source heat pump would run as long as outdoor temperatures are above freezing, and the gas boiler would heat when temperatures drop below 0°C (32°F), because the efficiency of an air-source heat pump decreases rapidly below freezing. For the transitional period, they also suggested a fireplace, which is not an issue since my wife wants one anyway.
In addition to the heating circuit described, we would like an automatic ventilation system with heat recovery. With our current knowledge, I would prefer the decentralized version. On the one hand, the initial investment is lower than with a central system (and very likely also the maintenance costs), and on the other hand, my uncle has a similar system in his house and has never reported any negative experiences.
I don't have the exact roof dimensions at hand right now, but the house has external measurements of 9m x 10m (30 ft x 33 ft) and a 45° pitched roof. By rough calculation, one half of the roof offers about 65m² (700 ft²) of space. We have been considering whether it makes sense to use only about two-thirds of that area for solar thermal and the rest for photovoltaic panels. This way, we could produce some of the electricity needed by the air-source heat pump ourselves.
That’s all I can think of for now.
We appreciate any advice, as I’m quite sure we have simply overlooked some points in our considerations so far. Also, I assume there are users here who know more about this than we do and have considerably more practical experience.
Best regards from the very sunny North!
H
HuggyLilly31 Jul 2013 07:30Dear AoR, dear experts,
I’m joining in here. Yesterday, I had the first meeting with a potential builder, who also recommended an air-to-water heat pump with domestic hot water (DHW) storage. I mentioned the low seasonal performance factor, but he said that based on his experience with his clients here, the results have been good so far. He roughly estimated that I should expect electricity costs of about 60 euros per month (for the pump). He advised me against the planned ground-source heat pump (geothermal heat pump), saying that the initial investment is too expensive (your keyword: "payback period"). I want to be independent of gas, but on the other hand, everything obviously has to remain affordable. He built a KfW 70-standard house for a friend; this friend later wanted to install a fireplace, and the chimney was already built during construction. But since the house is so well insulated, he has still not installed the fireplace today.
Next week, I will consult an independent energy advisor—let’s see what they recommend. I also planned to visit the consumer advice center quickly, but since they can cause uncertainty 😕, maybe better not after all.
I’m joining in here. Yesterday, I had the first meeting with a potential builder, who also recommended an air-to-water heat pump with domestic hot water (DHW) storage. I mentioned the low seasonal performance factor, but he said that based on his experience with his clients here, the results have been good so far. He roughly estimated that I should expect electricity costs of about 60 euros per month (for the pump). He advised me against the planned ground-source heat pump (geothermal heat pump), saying that the initial investment is too expensive (your keyword: "payback period"). I want to be independent of gas, but on the other hand, everything obviously has to remain affordable. He built a KfW 70-standard house for a friend; this friend later wanted to install a fireplace, and the chimney was already built during construction. But since the house is so well insulated, he has still not installed the fireplace today.
Next week, I will consult an independent energy advisor—let’s see what they recommend. I also planned to visit the consumer advice center quickly, but since they can cause uncertainty 😕, maybe better not after all.
The idea of being independent from gas may sound appealing, but does it really benefit you? Ultimately, while you free yourself from one energy source, a heat pump still requires electricity to operate, and a wood stove stays cold if you don’t add any wood.
Apart from that, it’s important to have a clear concept before deciding on an energy source. Although it’s a common argument that air-to-water heat pumps have a low annual performance factor (which is partly true), they can still provide quite efficient heating if the supporting components are properly matched—such as underfloor heating with low supply temperatures, proper insulation of the building envelope, and correct sizing of the unit itself.
Of course, there are systems that are even more efficient and incur lower operating costs, but whether those benefits justify the initial investment, maintenance demands, or simply fit your own convenience, is something everyone must decide for themselves.
Apart from that, it’s important to have a clear concept before deciding on an energy source. Although it’s a common argument that air-to-water heat pumps have a low annual performance factor (which is partly true), they can still provide quite efficient heating if the supporting components are properly matched—such as underfloor heating with low supply temperatures, proper insulation of the building envelope, and correct sizing of the unit itself.
Of course, there are systems that are even more efficient and incur lower operating costs, but whether those benefits justify the initial investment, maintenance demands, or simply fit your own convenience, is something everyone must decide for themselves.
H
HuggyLilly31 Jul 2013 18:11So how is it really with air-to-water heat pumps? You often read that below 0°C (32°F), only the electric heating element heats the buffer tank and the pump no longer supplies anything?
I live in the northwest, and it hasn’t been very cold for a long time, especially not continuously.
I live in the northwest, and it hasn’t been very cold for a long time, especially not continuously.
We have asked ourselves this question many times and learned that, to effectively assess the cost-benefit of a heating system, it is essential first to determine the heating load (if I remember the correct term) of the house.
That’s why we have moved away from overthinking the heating system for now and are waiting until we have more detailed information about our house. Then we will take the data to one or two heating installers and have them calculate and provide us with offers.
At the moment, we are still working on the floor plan.
That’s why we have moved away from overthinking the heating system for now and are waiting until we have more detailed information about our house. Then we will take the data to one or two heating installers and have them calculate and provide us with offers.
At the moment, we are still working on the floor plan.
H
HuggyLilly1 Aug 2013 20:29You’re probably right; but you have to do your research beforehand... and I’m very grateful to the experts here for their helpful advice. Today, I spoke with an acquaintance who is also a builder, and he said that going beyond the basics is often not worthwhile—just minimal effort to meet legal requirements and proper insulation. Otherwise, many things don’t pay off. So, I’m already giving up on the ground source heat pump and photovoltaic system. It will likely end up with a gas boiler and a solar thermal system for domestic hot water. At most, a water-heated fireplace, since I want a fire anyway; it will depend on the additional costs.
Similar topics