VRF in EE4 workaround

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Hello forum users,

I need to model a VRF system in EE4, I have read that there is no direct
way to do it so I was wondering whether anyone knew of a workaround/other
method to asses the energy performance of such a system.

Thanks in advance

*Juan Sebastian Carrizo*

Sebastian Carrizo's picture
Joined: 2013-11-06
Reputation: 0

Dear Juan,
I am not an EE$ user, but the approach below is one I used in EnergyPlus before it could model VRF. It may help you...

* VRF with heat recovery: A water source heat pump system does exactly the same functions as heat recovery VRF systems, but uses different equipment. To model the VRF:
o Assign fan power to match the VRF fan power
o We'll want all of the actual power use to be reflected at the System level, not zone level, so define the WSHP compressor with a COP of 10,000. That results in compressor power = load.
o The WSHP plant loop will have a Boiler and Chiller, and only one or the other will operate to meet the loop needs, just like VRF. Since neither of these have part load performance similar to the VRF outdoor unit, we want to make their energy use reflect loads only, and that requires boiler efficiency = 1.00 and chiller COP = 10,000. (Note: This could also be accomplished using District heating and cooling)
o After reporting the energy use for the boiler and chiller using Meter:Custom, apply the proper VRF part load factors in a post-process calculation.

James V Dirkes II, PE, BEMP, LEED AP

James V Dirkes II, PE's picture
Joined: 2011-10-02
Reputation: 203

Hi Juan,

It is pretty tough to simulate VRF in EE4 unless you take some workaround
by modifying Doe file and export hourly results. Post processing is

I strongly suggest that you should use Energypro (the same developer of EE4
if I am not wrong). Check this out



chen yu's picture
Joined: 2011-10-02
Reputation: 200

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Aaron Smith's picture
Joined: 2011-09-30
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