Hello!
I'll start.
Heated area 200m2 (2,153 sq ft)
KfW 55 standard
Mechanical ventilation with heat recovery
Current outdoor temperature 6°C (43°F)
Heating energy consumption including hot water 35 kWh
Electricity consumption 9 kWh
COP 3.88
I'll start.
Heated area 200m2 (2,153 sq ft)
KfW 55 standard
Mechanical ventilation with heat recovery
Current outdoor temperature 6°C (43°F)
Heating energy consumption including hot water 35 kWh
Electricity consumption 9 kWh
COP 3.88
Lumpi_LE schrieb:
What is stated in the energy performance certificate is not very meaningful.
In general, such comparisons are rarely helpful because too many factors are involved. I am aware that the information in the energy performance certificate does not allow for a direct one-to-one comparison.
But can’t you at least get a general idea? On the other hand, if someone has a heat transfer coefficient (Ht) of 0.2 and another has 0.3, you can assume that the building envelope in the first case has better insulation values, right?
Overall, I find this kind of guidance helpful as an orientation. Of course, they should not be compared directly, that’s clear to me.
There are one or two examples here of people who only started researching and optimizing after joining this forum.
So, I do find it quite useful.
T
T_im_Norden1 Feb 2021 13:45What is stated on the certificate can at best serve as a reference point, assuming all calculations were done correctly and the construction was carried out accordingly.
face26 schrieb:
If someone has an ht value of 0.2 and another has 0.3, you can assume that the building envelope in the first case has better insulation performance, right?Yes, you can assume that, but it is not necessarily the case and has little to do with heating consumption. Windows, sunlight, wind, indoor temperature, ventilation behavior, and neighboring buildings all have a greater impact than an ht value of 0.2 or 0.5, but these factors are difficult to assess.Analyzing the last 24 hours:
Outdoor temperature around 1°C (34°F)
Heat demand for the last 24 hours: 90 kWh (water and heating)
Electricity consumption: 24 kWh
90 / 24 = COP 3.75
That’s not completely off, but it’s also not great for a KFW55 house with a state-of-the-art air source heat pump. I would like to see it above 4.x.
I will perform a new hydraulic balancing once it gets colder, as I suspect there is a short circuit causing unnecessary energy loss.
Other than that, everything is already optimized as far as possible.
Outdoor temperature around 1°C (34°F)
Heat demand for the last 24 hours: 90 kWh (water and heating)
Electricity consumption: 24 kWh
90 / 24 = COP 3.75
That’s not completely off, but it’s also not great for a KFW55 house with a state-of-the-art air source heat pump. I would like to see it above 4.x.
I will perform a new hydraulic balancing once it gets colder, as I suspect there is a short circuit causing unnecessary energy loss.
Other than that, everything is already optimized as far as possible.
A
Alessandro2 Feb 2021 10:21Can you tell me how much power your UWP delivers?
Mine runs between 11 and 18 watts, which I find extremely low and makes me wonder.
I’m worried that the hot water in the pipes might “starve” or not circulate properly.
I still don’t know whether to set the UWP to constant pressure or proportional pressure when using ERR...
The links I found online are confusing, and everyone says something different :-P
Mine runs between 11 and 18 watts, which I find extremely low and makes me wonder.
I’m worried that the hot water in the pipes might “starve” or not circulate properly.
I still don’t know whether to set the UWP to constant pressure or proportional pressure when using ERR...
The links I found online are confusing, and everyone says something different :-P