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asked 2018-05-02 00:52:57 -0600

katsuya.obara's avatar

Why having unmet hour even though capacity is enough for VRF system?

I have model which implement VRF system using HVACTemplate:Zone:VRF and HVACTemplate:System:VRF.
I am having problem to reduce unmet hour as below. (Above graph:Indoor Unit Cooling Rate[W]/Below graph:Unmet hour for each zone) Since outdoor unit connected to these zone indoor unit has 35kW capacity, capacity should not be problem.
Does anyone know why and how to solve this problem?
image description
I also tried to change Master Thermostat Priority Control Type, but could not reduce unmet hour below 300 hours.

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updated 2018-05-02 07:46:46 -0600

Julien Marrec's avatar

Why having unmet hour even though capacity is enough for VRF system?

I have model which implement VRF system using HVACTemplate:Zone:VRF and HVACTemplate:System:VRF.
I am having problem to reduce unmet hour as below. (Above graph:Indoor Unit Cooling Rate[W]/Below graph:Unmet hour for each zone) Since outdoor unit connected to these zone indoor unit has 35kW capacity, capacity should not be problem.
Does anyone know why and how to solve this problem?

image description

I also tried to change Master Thermostat Priority Control Type, but could not reduce unmet hour below 300 hours.

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