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when using heat pump 927 the source outlet temp still remains high even if the load temp has increased to the req amount...its like source in is 80 source out is 80...load in is 40 load out is 120..........why the source out is not decreasing...it should acc to thermodynamics
@sw17032 There are a few things that might be worth checking.
first, are the source inlet and outlet temperature exactly the same value or are they very close to each other? If the flow rate on the source side is enormous in comparison the the quantity of energy being extracted from it then the temperature of the source side may not change a lot between its inlet and outlet.
second, Type927 relies on a performance map that contains values of heat pump capacity and COP as a function of the inlet load and source conditions. The model is able to interpolate within the range of inlet conditions contained in the performance map but it cannot extrapolate beyond the range. Instead it just holds onto the capacity and COP that is closest to the given inlet conditions. You can get some odd results back if you are applying inlet conditions that are way outside the range of the map that you are using.
if neither of those leads to a solution then I would recommend you contact your distributor's technical support hotline and send them a detailed description of the behavior you are seeing as well as your project and any other files that are needed in order to run it. If you aren't sure who to contact, please visit: https://sel.me.wisc.edu/trnsys/sales/distributors.html
kind regards,
David
sw17032 Topic starter
02/07/2025 7:25 am
@davidbradley actually i have kept all the specs same as default just only scale factor =1, no of heat pumps on =1, and rated heating capacity is 15KW those are the only changes i did from my side.... the source side is PVT loop, where in the output from PVT is 60-70C and inlet going back after passing from heat pump is also same not even 1°C of difference is there..
sw17032 Topic starter
02/07/2025 9:31 am
sorry for the delay in getting back to you. If there is a difference between the inlet and outlet temperature, even if it is very small then I do not think that there is a problem in the code. I think that the problem may lie in either the sizes/capacities of the equipment that you have chosen or that there might be some issues with the controls. If you have not done so already, I would recommend contacting your distributor's technical support hotline as they can take a look at your simulation and provide more specific feedback.
~david
