Modeling water cooled VRF

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Does anyone have an idea whether Trace can model a water cooled VRF system?

I need to model a system with VRF and a boiler / tower condenser water loop.


ebroemel's picture
Joined: 2011-05-06
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The help file states that you can't add a cooling tower to a "air to heat" pump. (I'm guessing that's a typo for "air to air"). You can add a boiler to a vrf plant as is (TRACE doesn't know the difference). Just remember to set the "minimum operating temperature" in the cooling equipment library.

The main difference here is the ambient relief though (since it would be based on wet-bulb instead of dry bulb). There's no direct way to do this, but you could just use the Chiller-heater, and ignore the evaporator side pumps, and other water cooled controls (ie, don't add chilled water reset).

The VRF plant assumes that it is just 1 large piece of equipment anyway.

Alternatively, you could modify the ambient relief curve for the VRF heat pump, and account for the cooling tower energy with a custom heat rejection device of the same power.

Bob F's picture
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