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Pumping circuits for the modeling of a reversible air to water HP in EnergyPlus

Hi !

I'm a beginner with EnergyPlus and I have to model a reversible air to water HP linked to an underfloor heating and cooling system, so I have a few questions.

I'm only using the IDF editor interface so far. I used the WaterHeater:HeatPump:PumpedCondenser object for the heating loop and an air-cooled electric chiller for the cooling loop.

I'm supposed to have two pumping circuits, one between the floor and a low loss header manifold and an other between this manifold and the heat pump. Therefore the flow through the heat pump is different to the floor. The low loss header is essentially a counterflow mixed heat exchanger.

This is what my SVG file looks like for now :

https://image.noelshack.com/fichiers/2017/39/2/1506387764-svg-file-energyplus-model10-1.png

For the heating loop, considering that the use side and source side of the water tank can have different flows, I think that should work without changing anything? I'm just not sure what capacity and volume I should use for the waterheater object. My guess would be 0 capacity (because the coil:waterheating:airtowaterheatpump:pumped is addressing the heating), and a low volume. Should I add a pump somewhere, maybe in the loop that links the HW tank and the condenser? Or is the condenser water pump included in the coil object enough?

For the cooling loop, I'm really not sure what to do. The way it is now doesn't feel right because I only have one pumping circuit. I was thinking I could replace the electric chiller object with a HeatExchanger:FluidtoFluid, and create an other loop linking that exchanger with the air cooled chiller. Would that work? Is there a better solution ?

And do I need a condenser loop in addition to the chiller:electric object to model the reverse cycle chiller correctly?

Well, I'm sorry I have that many questions, but as I said I'm beginning with the software and just out of the engineering school so I'm not confident yet about all this. If you spot anything else that could be wrong with my model please tell me !

I hope you can help me and thank you already !

Have a great day !

Regards,

Marylène

Pumping circuits for the modeling of a reversible air to water HP in EnergyPlus

Hi !

I'm a beginner with EnergyPlus and I have to model a reversible air to water HP linked to an underfloor heating and cooling system, so I have a few questions.

I'm only using the IDF editor interface so far. I used the WaterHeater:HeatPump:PumpedCondenser object for the heating loop and an air-cooled electric chiller for the cooling loop.

I'm supposed to have two pumping circuits, one between the floor and a low loss header manifold and an other between this manifold and the heat pump. Therefore the flow through the heat pump is different to the floor. The low loss header is essentially a counterflow mixed heat exchanger.

This is what my SVG file looks like for now :

https://image.noelshack.com/fichiers/2017/39/2/1506387764-svg-file-energyplus-model10-1.png

For the heating loop, considering that the use side and source side of the water tank can have different flows, I think that should work without changing anything? I'm just not sure what capacity and volume I should use for the waterheater object. My guess would be 0 capacity (because the coil:waterheating:airtowaterheatpump:pumped is addressing the heating), and a low volume. Should I add a pump somewhere, maybe in the loop that links the HW tank and the condenser? Or is the condenser water pump included in the coil object enough?

For the cooling loop, I'm really not sure what to do. The way it is now doesn't feel right because I only have one pumping circuit. I was thinking I could replace the electric chiller object with a HeatExchanger:FluidtoFluid, and create an other loop linking that exchanger with the air cooled chiller. Would that work? Is there a better solution ?

And do I need a condenser loop in addition to the chiller:electric object to model the reverse cycle chiller correctly?

Well, I'm sorry I have that many questions, but as I said I'm beginning with the software and just out of the engineering school so I'm not confident yet about all this. If you spot anything else that could be wrong with my model please tell me !

I hope you can help me and thank you already !

Have a great day !

Regards,

Marylène