Hello!
I have a large house, 20 radiators + UFH. Heated house area is about 350 m2. House is class B, it is written in the certificate that house requires 73 kWh(m2/year) for heating. I had my system fully upgraded last year, installed new Vitodens 200-W 49 kW (B2HA) model with Vitotronic 200 controls. I know I made a mistake when choosing boiler, I thought my model supports 1:17 modulation too, but unfortunately this is not the case with 49 KW version.
Last year I used it with Tado, but I didn't like Tado modulation, so I decided to give a try to Viessmann weather compensation this time. So, right now we have about +10 C outside, and my boiler short cycles unless I do 2 things - first I have to open all radiators and second, I have to insanely adjust heating curve, like we are talking about 1.3 slope and 12 level, so the temperature would be around 50 C when it is 10 C outside. When both this things are done, boiler starts, modulates and works for some time, after that some rooms with Tado TRV's are heated enough, radiators are closed now and boiler just stops, while half of the house is still cold.
After that boiler starts itself for 15 seconds each ~10 minutes, heats up to 55 C, turns the burner off and temperature (of course) drops immediately. Could it be that my boiler is simply too powerful for the system and cannot modulate low enough or there are other reasons for this behaviour?
Thank you all in advance.
I have a large house, 20 radiators + UFH. Heated house area is about 350 m2. House is class B, it is written in the certificate that house requires 73 kWh(m2/year) for heating. I had my system fully upgraded last year, installed new Vitodens 200-W 49 kW (B2HA) model with Vitotronic 200 controls. I know I made a mistake when choosing boiler, I thought my model supports 1:17 modulation too, but unfortunately this is not the case with 49 KW version.
Last year I used it with Tado, but I didn't like Tado modulation, so I decided to give a try to Viessmann weather compensation this time. So, right now we have about +10 C outside, and my boiler short cycles unless I do 2 things - first I have to open all radiators and second, I have to insanely adjust heating curve, like we are talking about 1.3 slope and 12 level, so the temperature would be around 50 C when it is 10 C outside. When both this things are done, boiler starts, modulates and works for some time, after that some rooms with Tado TRV's are heated enough, radiators are closed now and boiler just stops, while half of the house is still cold.
After that boiler starts itself for 15 seconds each ~10 minutes, heats up to 55 C, turns the burner off and temperature (of course) drops immediately. Could it be that my boiler is simply too powerful for the system and cannot modulate low enough or there are other reasons for this behaviour?
Thank you all in advance.
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