Question-and-Answer Resource for the Building Energy Modeling Community
Get started with the Help page
Ask Your Question

How to simulate the on/off time for an FCU using OS or E+?

asked 2018-11-12 00:30:33 -0600

Westely gravatar image

updated 2018-11-12 09:17:08 -0600

Hi all: I am working on an FCU serving an open office. I want to simulate the FCU working status, compare with the actual working status to check if they match. In my model, I have an indoor setting temperature, supply air temperature, etc. seems I can simulate the FCU working time because it should depend on the indoor temperature. but in OS, the FCU has a schedule, "Always On Discrete", I am not sure how it impacts the simulation. I was wondering know if there is any way to simulate the on/off time for the FCU using Open Studio or E+? or can I decide the time using the simulated temperature? Thanks and any comments are welcome!

edit retag flag offensive close merge delete

1 Answer

Sort by ยป oldest newest most voted

answered 2018-11-12 01:32:04 -0600

See the ZoneHVAC:FourPipeFanCoil object documentation in the E+ Input/Output reference.

Availability Schedule:

"The name of the schedule (ref: Schedule) that denotes whether the fan coil unit can run during a given time period. A schedule value greater than 0 (usually 1 is used) indicates that the component can be on during the time period. A value less than or equal to 0 (usually 0 is used) denotes that the component must be off for the time period. If this field is blank, the schedule has values of 1 for all time period"

The fan coil will turn on when:

1) There is a zone request to serve a heating or cooling load, and

2) the fan coil is available to run per the availability schedule.

See the E+ engineering reference for more details on how zone HVAC equipment is controlled.

To determine run time, set the Capcity Control Method input to CyclingFan, and add the HVAC,Average,Fan Coil Runtime Fraction Output Variable.

edit flag offensive delete link more

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer


Question Tools

1 follower


Asked: 2018-11-12 00:30:33 -0600

Seen: 27 times

Last updated: Nov 12