ᐅ Installation of a Gas Heating System in New Construction 2023/2024

Created on: 11 Apr 2023 14:47
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robert0815
Hello fellow home builders,

we have started constructing a single-family house. The approved building permit / planning permission includes a gas heating system, which we still want to install.

There are two possible scenarios:

1. What happens if the heating system is installed in October 2023, but the house is only inspected and approved in February 2024?

2. What happens if the heating system is installed in January 2024, and the house is inspected and approved in May 2024?

Both options are difficult to plan for. So far, we do not know whether the construction schedule might be delayed.
I haven't found any information on this. Do you have any further details?

Regards,
robert0815
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Bookstar87
4 May 2023 21:32
Buschreiter schrieb:

The heat pump will be defective after at most 20 years and a total economic loss…
Most heat pumps won’t last 20 years, rather about 10 years.
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Buschreiter
5 May 2023 07:09
At least the guild mentions about 15 years. For future heat pumps, I would expect greater durability… also from a sustainability perspective.
Tolentino5 May 2023 07:18
Why should they break down so quickly? We have a refrigerator that is over 15 years old. It recently started making strange noises, but it still cools. It will be replaced soon for efficiency reasons.

Another reason I can imagine is that heat pumps with a seasonal performance factor (SPF) of 3.5–4.5 are considered insufficient, while new ones operate at 7–8 SPF. This might lead to replacing them either voluntarily or due to legal incentives before a total failure occurs.
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Bookstar87
5 May 2023 07:56
I think it's because the initial startup phase usually runs really poorly and the compressor has to cycle very frequently. Statistically, the pumps end up wearing out after 10 years, even though they could actually last twice as long.

It would be interesting to know what is physically possible. An annual performance factor (APF) of 8 would be amazing.
andimann5 May 2023 13:09
Hello,
Bookstar87 schrieb:

It would be interesting to know what is physically possible.

That’s relatively simple. Look up Carnot efficiency and the second law of thermodynamics...

With the temperature levels of an air-to-water heat pump, you can theoretically reach maximum values of around 8–10. But that’s in an ideal process without any flow losses, perfect energy transfer, constant temperature levels, and continuous operation of the system. When you factor in real-world conditions, you will probably manage to reach around 5–5.5 with a lot of effort and care. After that, it’s basically impossible. You can definitely forget about an annual performance factor of 8.

Best regards,

Andreas
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Buschreiter
5 May 2023 14:03
Tolentino schrieb:

Why should they break down so quickly? We have a refrigerator that is over 15 years old.
It has been making strange noises recently, but it still cools.

If a heat pump starts making strange noises, it might be time to check it… which would be more important to me than a refrigerator! As already mentioned, all experts say that heat pumps generally have a shorter lifespan than gas boilers, possibly also due to oversizing by the installer (the usual “we’ve always done it this way…”), causing the system to cycle on and off too frequently. That would at least be a plausible reason!