Re: [EnergyPlus_Support] Low Temp Radiant System Inside Surface Temperatures

[Rick Strand <rkstrand@xxxxxxxxxxxx>]

There are a variety of ways in which you could increase the temperature of the surface in which your radiant system is embedded.  Your actual temperature will, as I am sure you are aware, will depend greatly on the space it resides in, the connections to the outside environment, the outside environment, and the construction of the zone and floor.
Increasing the water supply temperature and increasing the flow rate of water to the system would be your best options for getting an increased temperature at the floor surface.  Increasing the tube length would potentially result in more heat transfer, but there is a limit to this and most input files will not show a significant impact on the surface temperature by changing only the tube length.
I hope this helps.
Rick Strand
EnergyPlus Development Team

On Jan 22, 2009, at 10:07 AM, Elreq wrote:
> 
> Dear Forum,
> 
> I have the following problem:
> 
> I am modeling an underfloor heating & cooling system using the object:
> Low temperature radiant system: constant flow. It works fine, but if I
> select the surface under which the radiant tubing is embedded, in this
> case a floor of a zone, and I see the inside temperatures, this are
> not as high as they should be due to the hot water flowing through the
> tubes. The temperatures increases when the heating rate increases but
> I expect to see some temperatures around 28 degrees or so, but they
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