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Mantra, I'm updating my answer with some new info that might help you.

1) In the first figure, you can find the outputs related to the "floor's interior surface temp.", "floor's exterior surface temp", "VRF cooling load", and "floor's heat transfer rate through conduction". I performed the simulation based on Jodhpur weather file since I didn't have Bali's weather file.

2) As you can see, the cooling peak load (blue graph) occurs around May 25th, where the corresponding interior surface temperature is around 26.5C.

3) The yellow line shows that the outside temperature is constant (24C) throughout the year.

4) The second figure shows a simple calculation based on "heat transfer rate" and the "interior surface temp" exported from the first figure to an Excel sheet. It shows that the U-value is almost constant and it is about 10 W/m2k. The fluctuations are due to the changes in the air film's properties; however, the overall U-value is still very high.

So, it shows that the calculations are correct and whatever is causing the big numbers, is related to the material properties or to be more accurate the conductions. image description

image description

Mantra, I'm updating I update my previous answer with some new info that might help you.

1) In the first figure, because it is too long for a comment. Here are a few notes:

1)Changing the 20C has no impact on the number you are looking at (4000W). Because the 4000W is for "cooling load" (see the top of that table). So, the only number that can find the outputs related to the "floor's interior surface temp.", "floor's exterior surface temp", "VRF cooling load", and "floor's have an impact on the floor's heat transfer rate through conduction". I performed the simulation based on Jodhpur weather file since I didn't have Bali's weather file.

2) As is your cooling setpoint (24C).

2)The section that you can see, the cooling peak load (blue graph) occurs around May 25th, where the corresponding interior surface temperature is around 26.5C.

3) The yellow line shows that the outside temperature is constant (24C) throughout the year.

4) The second figure shows a simple calculation based on "heat transfer rate" and the "interior surface temp" exported from the first figure to an Excel sheet. check does not report total or annual average heat transfer. It shows that the U-value is almost constant the cooling "peak loads". It is just for the peak demand.

3)Basically, this number (4000W) shows that during the peak cooling load, the ground is acting as a cold surface and collects the heat from indoor (that's why it is about 10 W/m2k. The a negative number).

4)So, the number could be correct. You can check the hourly fluctuations in the indoor air temperature to see when the peak cooling load occurs and that would be the number used to calculate that 4000W.

5)Bear that in mind that these numbers are due to the changes in the air film's properties; however, the overall U-value is still very high.

So, it shows that the calculations are correct and whatever is causing the big numbers, is related to the material properties or to be more accurate the conductions. estimations. Read this image description

image description

for further info.

side note: your heating load is zero. Make sure your HVAC system is defined properly.

Mantra, I update my previous answer because it is too long for a comment. Here are a few notes:

1)Changing the 20C has no impact on the number you are looking at (4000W). Because the 4000W is for "cooling load" (see the top of that table). So, the only number that can have an impact on the floor's heat transfer is your cooling setpoint (24C).

2)The section that you check does not report total or annual average heat transfer. It shows the cooling "peak loads". It is just for the peak demand.

demand. 3)Basically, this number (4000W) shows that during the peak cooling load, the ground is acting as a cold surface and collects the heat from indoor (that's why it is a negative number).

4)So, the number could be correct. You can check the hourly fluctuations in the indoor air temperature to see when the peak cooling load occurs and that would be the number used to calculate that 4000W.

5)Bear that in mind that these numbers are estimations. Read this for further info.

side note: your heating load is zero. Make sure your HVAC system is defined properly.

Mantra, Based on the numbers I update my previous answer because it see in your "SlabBTID" file, I think there is too long for a comment. Here are a few notes: something wrong with the thermal conductivity. For example:

1)Changing the 20C has no impact on the number you are looking at (4000W). Because the 4000W is for "cooling load" (see the top of that table). So, the only number that can have an impact on the floor's heat transfer is your cooling setpoint (24C).2, !- TCON: Slab k {W/m-K}

2)The section It basically means that you check does not report total or annual average heat transfer. It shows for a 20cm slab, your U value is about 10 W/m2.K. Means the cooling "peak loads". It RSI is just for the peak demand. 3)Basically, this number (4000W) shows that during the peak cooling load, the ground about 0.1, which is acting as a cold surface and collects the heat from indoor (that's why it is a negative number).very low.

4)So, I hope that helps to solve the number could be correct. You can check the hourly fluctuations problem. If not, let me know and I will look at your file in the indoor air temperature to see when the peak cooling load occurs and that would be the number used to calculate that 4000W.more details.

5)Bear that in mind that these numbers are estimations. Read this for further info.

side note: your heating load is zero. Make sure your HVAC system is defined properly.