Problems with Radiant Panel Heating

asked 2017-06-16 05:14:07 -0500

reynoldsj8 gravatar image

updated 2017-06-19 05:26:37 -0500

So, I have quite a large complex school building where most of the zones are heated by radiant panels and some by VRF. Initially the gas consumption was very low (peak around 20kW when we expect over 200kW). The "Heating Control Temperature Schedule" is set to provide 40°C flow. All of the flows and heating capacities are set to autosize for the panel objects themselves based on the heating design days.

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The inlet and outlet node temperatures to the radiant panel objects were very low and did not recover overnight. Therefore, I changed the boiler water flow rates and the loop flow rates to autosize as they were too low. Now I get a very strange energy profile over 10 days in October.

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Despite this very low energy consumption somehow the zone temperatures are broadly OK and the inlet and outlet node temperatures remain very high. The zones temperatures have increased compared to previous iterations but energy consumption has decreased?

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I am now very confused with this model and any tips about modelling and controlling radiant panels in conjunction with a wider heating system would be greatly welcomed. Thanks in advance.

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