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low temperature radiator

Hello Everybody, I am trying to assess the effect of supply temperature in Radiators. For example, I would like to see if it is possible to reach a certain temperature (20 °C in winter) when a thermal zone is heated using high-temperature radiators and low-temperature radiators. In this case, the system is hydronic. In reality, it should be expected that a low-temperature heating system requires better insulation and energy performance of the building overall. But I am not sure how to set this up.

I started setting up a District Heating Loop as explained here first: https://unmethours.com/question/12845/openstudio-district-heating-and-cooling/

Now the problem is that I am not sure which type of heating distribution system to use. I have started running some simulations using basically a box and two windows per side to understand the effects of the different parameters. Right now I am using "Zone HVAC Baseboard Rad Conv Water". I have tried to change some settings for the Baseboard and the loop temperatures.

I was careful to not have any Severe Errors where the inlet temperature was lower than the outlet temperature.

The main thing I get is that when lowering the average temperature of the radiator to 40 °C and its radiant fraction to 0.1, during the coldest days, the Zone Temperature reaches 19 °C instead of 20 °C. That is not too much of a difference. In reality, 1 °C is enough to be felt, of course. But it is not that much to go from comfortable to very uncomfortable. And definitely not enough to justify a renovation of the envelope.

I am not sure I am performing this task correctly. Is there anyone who has had some previous experience with hydronic low-temperature heating?

Thank you very much in advance for your help! I wish you all a great day!

Regards, Luca C.

low temperature radiator

Hello Everybody, Everybody,

I am trying to assess the effect of supply temperature in Radiators. For example, I would like to see if it is possible to reach a certain temperature (20 °C in winter) when a thermal zone is heated using high-temperature radiators and low-temperature radiators. In this case, the system is hydronic. In reality, it should be expected that a low-temperature heating system requires better insulation and energy performance of the building overall. But I am not sure how to set this up.

I started setting up a District Heating Loop as explained here first: https://unmethours.com/question/12845/openstudio-district-heating-and-cooling/

Now the problem is that I am not sure which type of heating distribution system to use. I have started running some simulations using basically a box and two windows per side to understand the effects of the different parameters. Right now I am using "Zone HVAC Baseboard Rad Conv Water". I have tried to change some settings for the Baseboard and the loop temperatures.

I was careful to not have any Severe Errors where the inlet temperature was lower than the outlet temperature.

The main thing I get is that when lowering the average temperature of the radiator to 40 °C and its radiant fraction to 0.1, during the coldest days, the Zone Temperature reaches 19 °C instead of 20 °C. That is not too much of a difference. In reality, 1 °C is enough to be felt, of course. But it is not that much to go from comfortable to very uncomfortable. And definitely not enough to justify a renovation of the envelope.

I am not sure I am performing this task correctly. Is there anyone who has had some previous experience with hydronic low-temperature heating?

Thank you very much in advance for your help! I wish you all a great day!

Regards, Luca C.

low temperature radiator

Hello Everybody,

I am trying to assess the effect of supply temperature in Radiators. For example, I would like to see if it is possible to reach a certain temperature (20 °C in winter) when a thermal zone is heated using high-temperature radiators and low-temperature radiators. In this case, the system is hydronic. In reality, it should be expected that a low-temperature heating system requires better insulation and energy performance of the building overall. But I am not sure how to set this up.

I started setting up a District Heating Loop as explained here first: https://unmethours.com/question/12845/openstudio-district-heating-and-cooling/

Now the problem is that I am not sure which type of heating distribution system to use. I have started running some simulations using basically a box and two windows per side to understand the effects of the different parameters. Right now I am using "Zone HVAC Baseboard Rad Conv Water". I have tried to change some settings for the Baseboard and the loop temperatures.

I was careful to not have any Severe Errors where the inlet temperature was lower than the outlet temperature.

The main thing I get is that when lowering the average temperature of the radiator to 40 °C and its radiant fraction to 0.1, during the coldest days, the Zone Temperature reaches 19 °C instead of 20 °C. That is not too much of a difference. In reality, 1 °C is enough to be felt, of course. But it is not that much to go from comfortable to very uncomfortable. And definitely not enough to justify a renovation of the envelope.

I am not sure I am performing this task correctly. Is there anyone who has had some previous experience with hydronic low-temperature heating?

Thank you very much in advance for your help! I wish you all a great day!

Regards, Luca C.

low temperature radiator

Hello Everybody,

I am trying to assess the effect of supply temperature in Radiators. For example, I would like to see if it is possible to reach a certain temperature (20 °C in winter) when a thermal zone is heated using high-temperature radiators and low-temperature radiators. In this case, the system is hydronic. In reality, it should be expected that a low-temperature heating system requires better insulation and energy performance of the building overall. But I am not sure how to set this up.

I started setting up a District Heating Loop as explained here first: https://unmethours.com/question/12845/openstudio-district-heating-and-cooling/

Now the problem is that I am not sure which type of heating distribution system to use. I have started running some simulations using basically a box and two windows per side to understand the effects of the different parameters. Right now I am using "Zone HVAC Baseboard Rad Conv Water". I have tried to change some settings for the Baseboard and the loop temperatures.

I was careful to not have any Severe Errors where the inlet temperature was lower than the outlet temperature.

The main thing I get is that when lowering the average temperature of the radiator to 40 °C and its radiant fraction to 0.1, during the coldest days, the Zone Temperature reaches 19 °C instead of 20 °C. That is not too much of a difference. In reality, 1 °C is enough to be felt, of course. But it is not that much to go from comfortable to very uncomfortable. And definitely not enough to justify a renovation of the envelope.

I am not sure I am performing this task correctly. Is there anyone who has had some previous experience with hydronic low-temperature heating?

Thank you very much in advance for your help! I wish you all a great day!

Regards, Luca C.