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Modeling Air to water heat pump with fan coil unit

asked 2017-10-04 03:07:43 -0500

dana's avatar

Hi, I started to learn how to model the energy plus with design builder. What I am trying to do now is, to model the air to water heat pump system with the fan coil unit. Is it possible to make a model with energy plus and do you guys have any tips for the fast modeling?

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answered 2017-10-26 11:35:05 -0500

There is not currently a central plant air-to-water heat pump in EnergyPlus. Use an air-cooled chiller to supply the chilled water loop and a heat pump water-heater to supply the hot water loop. Use availability managers on the plant loops to prevent them from both operating at the same time.

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answered 2019-10-02 09:05:17 -0500

I'm bumping into this two years later, and good news is that it's coming soon:

In the meantime, I can propose another (untested) workaround.

The major issue with the workaround by @MJWitte is that there's no easy way to model the "heat recovery" (when you need both cooling and heating at the same time), which is the principle advantage of the so-called 6-pipe heat pump systems.

I think another alternative would be to use a CentralHeatPumpSystem. You probably know already that this object is meant to model geothermal application, but it means it expects to have a condenser Plant Loop. You could put a District Heating and a District Cooling, and a pump, on the condenser loop, making sure they have infinite capacity, but you'll have to zero-out their consumption. Then you put a SetpointManager:FollowOutdoorAirTemperature on the supply outlet.

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Julien, (or @MJWitte) do you happen to know if the new air-source EIR WWHP will be able to simulate "heat recovery" (i.e. simultaneous heating/cooling, bypassing the air condenser)? The design document and proposed input changes don't indicate anything to that effect.

ericringold's avatar ericringold  ( 2019-10-02 12:20:26 -0500 )edit

So that's a "no'.

ericringold's avatar ericringold  ( 2019-10-03 12:10:42 -0500 )edit

Yep, it's a no.

Julien Marrec's avatar Julien Marrec  ( 2019-10-04 02:20:55 -0500 )edit

Is there an update on the air-to-water heat pump model? It looks like its not yet implemented in Energy Plus, does anyone know the status on that?'s avatar  ( 2020-12-07 05:09:41 -0500 )edit

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Asked: 2017-10-04 03:07:43 -0500

Seen: 1,823 times

Last updated: Oct 02 '19