Issues with imported CSV heating and cooling demand

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tstesco
Beiträge: 2
Registriert: Mo Nov 06, 2017 6:15 pm

Di Nov 07, 2017 6:10 pm

We followed the docs page 121 section 3.5.2 for importing the heating profile from a CSV file, how ever we have both heating and cooling at the same time in our large commercial building and are looking for a way to simulate this in polysun. Currently we have a different template for each cooling and heating but this is not ideal. Also, we are uncertain how the set point temperature in the demand profile is being used during computation.

Also, we noticed that with our DHW profile the demand did not change unless we also changed the annual demand parameter in the GUI. When we set it to the sum of our hourly demand CSV it gives us the correct demand, though the flow rate is uniform across the year. Is the flow rate used in energy computations?

Lars Kunath
Beiträge: 91
Registriert: Do Mär 02, 2017 2:35 pm

Mi Nov 08, 2017 8:40 am

Dear tstesco,

heating and cooling cannot uploaded in one profile. The way to calculated it would be to use a system template where you have a heating loop and a cooling loop with two buildings and two heating/cooling elements. Than you can define one building as "cooling demand" and one as "heating demand".

The set point temperature is a synthetic temperature which helps to calculate the required inlet temperature of the heating/cooling element. For Europe you can use values around 12 °C for areas closer to the equator you can use 15 °C for heating 21 °C

When you change a DHW profile you are only changing the time when you are consuming hot water (morning, afternoon...?), you are not changing the quantity. To change the quantity you need to change annual demand (as you did).
In case of using an hourly profile you can change the quantity within this profile. You can check out this video from minute 4:25: https://www.youtube.com/watch?time_cont ... tU7I1H_HVQ (unfortunately German)

Hope this helps you!

tdanai
Beiträge: 3
Registriert: So Nov 05, 2017 6:22 pm

Sa Nov 11, 2017 7:00 pm

Lars Kunath hat geschrieben:
Mi Nov 08, 2017 8:40 am

The set point temperature is a synthetic temperature which helps to calculate the required inlet temperature of the heating/cooling element. For Europe you can use values around 12 °C for areas closer to the equator you can use 15 °C for heating 21 °C
For a building that needs to be at 21°C when occupied and 17°C when unoccupied, are those two the right values to use in the hourly demand file?

Also, the hours that have 0 heating demand, even though the setpoint is set according to occupancy, in the tabular matrix it shows that the program turns the setpoint automatically to 20°C. Why is that? From where can it be controlled?

yihe
Beiträge: 4
Registriert: Sa Nov 04, 2017 3:48 pm

So Nov 12, 2017 3:02 pm

Hi tom, where did you find the documentations? We have the same problem but we can't find the documentation about it.

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