Is the heating oversized?

2016-01-18 22:28:03

According to the Energy Saving Ordinance, I have a ht of 0.285. What is it with you? That also clarifies why everyone says, do a heating load calculation and don't come to me with Energy Saving Ordinance papers. No, but apart from that, there are so many assumptions in the calculation that are actually not correct; starting with flat thermal bridge values, it says "windows with Uw<1.00 (we are well below that in reality), perimeter/basement insulation became 0.035 instead of 0.038. I calculated with the actual materials, dimensions, etc. of the planning for the construction site, according to the tenders, so it was naturally more accurate.

2016-01-18 22:38:31

According to the Energy Saving Ordinance, we ended up at 0.246 – however, the esteemed gentlemen on the ground floor replaced 2 cm of insulation with 2 cm of screed... therefore it will probably be slightly worse.

2016-01-19 08:03:39

It makes little sense to keep a low-temperature surface heating system turned off in large parts. The entire house should be evenly tempered. The system is not designed to operate only briefly. Aside from that, the produced heat must also be able to be delivered by the heat generator = either into a buffer storage or into the water reservoir of the entire underfloor heating system. If these heat storage units are no longer available, the heat generator must switch off. Either the heat generator does not match your system (too oversized) or your user behavior does not fit the system. I think both are possible if the gas condensing boiler cannot modulate down to a significantly lower output.

I don't have many options to influence it... in each room there is a controller set to about 20 degrees... once this is reached, the flow is automatically stopped by the controller + actuator...??? The only option = set all controllers to max... then they stay open continuously... and it gets too warm...

2016-01-19 08:08:49

I didn't see in the documents for your heating system where the minimum modulating output is. I probably just overlooked it and will simply estimate: 4-5 kW. That is too much for a modern house of the size of your property.

Best regards
Thorsten

Heating capacity kW
22
Modulation range kW
7.3 –21.8
Max. flow temperature °C
88
Domestic hot water capacity kW
28
Storage capacity l
100
Performance factor (DIN 4708) NL
2.8
Weight kg
108.3

2016-01-19 08:24:05

Only possibility = set all controllers to max... then they stay open permanently... and it gets too warm...

then adjust the heating curve on the heat pump (set the flow temperature lower) until only your desired temperature is reached. Then it fits and your heat pump only consumes the energy it really needs. However, according to my layman's estimate, the heat pump is also oversized.

2016-01-19 08:30:18

Heat pump? That's a gas heating system! But the heating curve definitely needs to be lowered then. But 7kw minimum is already quite a lot for a small house nowadays.

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Is the heating oversized?

Saruss

Legurit

Basti2709

Basti2709

Jochen104

Saruss