Partition Heat Flow, Hevacomp

RE: Partition Heat Flow, Hevacomp

Shane Regan — Mon, 19 Jul 2021 15:17:34 GMT

Hi Omar,

I did indeed, many thanks! Hope you did too. It will be hard to tell for certain without seeing the project files but I expect that the calculation is performing correctly in this case, as the heat Loss calc will take the design temperature figure from either the Winter design temperature shown below, or, from the profile if that is selected.

Have you selected the same profiles in this room and its surrounding adjoining rooms?

Regards,

Shane

RE: Partition Heat Flow, Hevacomp

Omar Elrouby — Mon, 19 Jul 2021 14:44:00 GMT

Hello Shane.

Hope you had a good weekend, with the nice weather.

Unfortunately I am not allowed to share the model files.

I think I have found the problem. The temperature gradients across the room seem to be established when I use the occupancy and temperature profiles attached.

These gradients become zero when I use a constant temperature for the thermal profiles i.e. my wanted temperature is 24 so I just set it to be 24 across all hours of the day.

Any idea why this is happening?

Many Thanks, Omar Elrouby.

RE: Partition Heat Flow, Hevacomp

Shane Regan — Fri, 16 Jul 2021 08:18:35 GMT

Hi Omar, these issues can often take a while to get to the root of so having the project to troubleshoot here usually works better - it is difficult to do this via Teams. I would most likely also need to change data in the project to check "root-vs-cause" so I would be adverse to doing this on the working project on your machine. If you can forward it I can take a look straight away, and if any subsequent issues arise I am more than happy to discuss afterward.

RE: Partition Heat Flow, Hevacomp

Omar Elrouby — Fri, 16 Jul 2021 07:24:08 GMT

Is it possible to arrange a quick teams call anytime you are free next week to discuss this and I can share screen and show you any parts you require?

Many Thanks, Omar Elrouby.

RE: Partition Heat Flow, Hevacomp

Shane Regan — Thu, 15 Jul 2021 15:27:17 GMT

Hi Omar,

Many thanks for clarifying - I see you are using the Heat Loss calculation, I had the CIBSE Gain calc in mind previously.

To be certain of the reasons I can examine the project if you could forward it? Please upload the project folder to this link.

RE: Partition Heat Flow, Hevacomp

Omar Elrouby — Thu, 15 Jul 2021 07:32:53 GMT

Hello, and good morning.

I have attached the drawing as well as the temperature differences across the partitions of room 43. Again I am confused why there is a temperature difference across the partitions. I have set the temperature in each of the rooms to be identical, hence the temperature difference should be 0.

The partition type is the adjacent room one, which I think is the correct partition to assign based on your previous reply.

Many thanks, any help much appreciated.

RE: Partition Heat Flow, Hevacomp

Shane Regan — Wed, 14 Jul 2021 14:26:03 GMT

Hi Omar, you can find details on the partition types in the manuals (accessed here) as below:

Could you please send a screenshot of the results you are referring to that shows what you describe - ie:

"the central room has a temperature differences across its partition's to the other rooms"

Are you referring to Fabric Loads in CIBSE Gain?

RE: Partition Heat Flow, Hevacomp

Omar Elrouby — Wed, 14 Jul 2021 11:02:38 GMT

Hi. I seemed to have solved it by using a Specified Temps partitions (before it was set to Adjacent Room partition, as the room is adjacent to another one).

Could you please elaborate on the different types of partitions available and what they do?

Many Thanks, Omar Elrouby.

RE: Partition Heat Flow, Hevacomp

Omar Elrouby — Wed, 14 Jul 2021 10:40:01 GMT

Hi, thanks for your reply.

It is true they will have different heat gains etc. However if the temperatures are the same then there should be no temperature differences between the rooms, hence partitions which are between adjoining rooms.

So do you know why there could be a temperature difference between the rooms even though the temperatures are set to be identical in these rooms?

Many Thanks.

RE: Partition Heat Flow, Hevacomp

Shane Regan — Wed, 14 Jul 2021 10:13:13 GMT

Hi Omar,

The rooms will have heat flow as they have different occupancies / gains defined, according to their characteristics such as area and room type.

Are you referring to the Design Temperatures in the room data? If so these are used thereafter to compute the required air flow in the calcs (eg at end of CIBSE Gain calc).

Regards,

Shane