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2019-05-20 12:50:39 -0500 commented answer Warning design cooling coil US

The warnings relate to: "Integrated Part Load Value (IPLV) calculated is not at the AHRI test condition". The CAPFT and

2019-05-16 07:22:12 -0500 commented answer Plant loop turn on/off chiller in same plant loop

I would add that this technique should also be used for the cooling coils (using set point temperature schedules or avai

2019-05-03 13:01:45 -0500 commented answer Water-Cooled VRF Not Meeting Heating Load

In your description you say "where the condenser loop gets too cold and the VRF shuts off". Is the boiler large enough t

2019-05-03 11:29:57 -0500 edited answer Water-Cooled VRF Not Meeting Heating Load

This is a little confusing. You say that the condenser loop is always active. This means that the supply side (the air i

2019-05-02 14:56:22 -0500 edited answer Can not access output variables for battery

The report variables you show are only used with a buss type that includes storage. The buss types ending with the word

2019-05-02 14:56:01 -0500 answered a question Can not access output variables for battery

The report variables you show are only used with a buss type that includes storage. The buss types ending with the word

2019-04-29 10:08:48 -0500 edited answer Conditioned and Unconditioned Spaces

In version 9.1 the EAp2-1. Space Usage Type table shows the same area as the Building Area table at 6328.86 m2 and 2396.

2019-04-29 10:07:54 -0500 answered a question Conditioned and Unconditioned Spaces

In version 9.1 the EAp2-1. Space Usage Type table shows the same area as the Building Area table at 6328.86 m2 and 2396.

2019-04-26 17:04:08 -0500 commented question Conditioned and Unconditioned Spaces

If the numbers are right in the Building Area table, then they are wrong in the EAp2-1 table. Send your E+ input file (*

2019-04-26 15:28:09 -0500 answered a question Multiplying Capacities? when using Multipliers

Upsizing the HVAC system to meet the multiplied load is the correct approach. I would suggest using autosize for all aut

2019-04-26 07:53:59 -0500 commented answer How to keep air loop flow rate as the one imposed by schedule? and not automatically varied according to cooling load

I was asking what values were entered for the Min/Max Outdoor Air Flow Rate fields. The schedule names are entered in th

2019-04-26 07:53:52 -0500 commented answer How to keep air loop flow rate as the one imposed by schedule? and not automatically varied according to cooling load

I was asking what values were entered for the Min/Max Outdoor Air Flow Rate fields. The schedule names are entered in th

2019-04-26 07:51:54 -0500 commented answer How to keep air loop flow rate as the one imposed by schedule? and not automatically varied according to cooling load

I was asking what values were entered for the Min/Max Outdoor Air Flow Rate fields. The schedule names are entered in th

2019-04-23 08:51:59 -0500 commented answer How to plot times SimHVAC exceeded max iterations?

Those check values mean roughly the same thing just in different terms/parameters. Look at the third one for mass flow r

2019-04-23 08:50:50 -0500 commented answer How to plot times SimHVAC exceeded max iterations?

Those check values mean roughly the same thing just in different terms/parameters. Look at the third one for mass flow r

2019-04-22 07:39:33 -0500 answered a question How to plot times SimHVAC exceeded max iterations?

There are a couple report variables that can be used for this purpose. Output:Variable,*,Air System Simulation Maximum

2019-04-22 07:22:49 -0500 commented answer VRF templates : How to fix these error: "Gross Rated Total Cooling Capacity [W] will be limited by the maximum rated volume flow per rated total capacity ratio"

I would say, especially for DX equipment, that starting with a reasonable delta T is important. Most of the DX models ha

2019-04-18 13:39:53 -0500 commented answer How to keep air loop flow rate as the one imposed by schedule? and not automatically varied according to cooling load

OK then, so the supply air temperature increases when the coil cannot meet the load and the VAV dampers open to compensa

2019-04-18 13:39:17 -0500 commented answer How to keep air loop flow rate as the one imposed by schedule? and not automatically varied according to cooling load

OK then, so the supply air temperature increases when the coil cannot meet the load and the VAV dampers open to compensa

2019-04-18 12:52:48 -0500 commented answer How to keep air loop flow rate as the one imposed by schedule? and not automatically varied according to cooling load

So the question is then why is the air loop air flow rate increasing (which will increase OA flow) when the load is grea

2019-04-18 12:38:09 -0500 commented answer Chiller loop getting to 322C in first timestep of design day and causing Severe error

The zone timestep is set here (and 4 timesteps per hour is the same as 15 minutes per timestep): Timestep, 4;

2019-04-18 12:36:03 -0500 commented answer Chiller loop getting to 322C in first timestep of design day and causing Severe error

There is a zone (building) timestep and a system (HVAC and plant) timestep. These can be adjusted in this object: Conve

2019-04-18 11:53:31 -0500 edited answer ** Severe ** ExternalInterface: Did not find file "socket.cfg". ** ~~~ ** This file needs to be in same directory as in.idf.

I Google this question and found this from Thierry Stephane Nouidui, PhD at the Simulation Research Group Lawrence Berke

2019-04-18 11:52:43 -0500 edited answer ** Severe ** ExternalInterface: Did not find file "socket.cfg". ** ~~~ ** This file needs to be in same directory as in.idf.

I Google this question and found this from Thierry Stephane Nouidui, PhD at the Simulation Research Group Lawrence Berke

2019-04-18 11:50:53 -0500 answered a question ** Severe ** ExternalInterface: Did not find file "socket.cfg". ** ~~~ ** This file needs to be in same directory as in.idf.

I Google this question and found this from Thierry Stephane Nouidui, PhD at the Simulation Research Group Lawrence Berke

2019-04-18 11:35:06 -0500 answered a question Chiller loop getting to 322C in first timestep of design day and causing Severe error

The only equipment in a chilled water loop that should add heat to the loop is the pump. I suggest adding: Output:Diagn

2019-04-18 10:27:46 -0500 commented answer VRF templates : How to fix these error: "Gross Rated Total Cooling Capacity [W] will be limited by the maximum rated volume flow per rated total capacity ratio"

@Alexis, lower the cooling supply air temperature to decrease zone cooling air flow rate.

2019-04-18 09:13:38 -0500 commented answer VRF templates : How to fix these error: "Gross Rated Total Cooling Capacity [W] will be limited by the maximum rated volume flow per rated total capacity ratio"

Please show the Zone Sizing Information for 2 different simulations using different supply air temperature for sizing so

2019-04-18 08:28:18 -0500 commented answer How to keep air loop flow rate as the one imposed by schedule? and not automatically varied according to cooling load

Did you enter a schedule name with values of 1 into these 2 fields?

2019-04-18 08:21:32 -0500 commented answer VRF templates : How to fix these error: "Gross Rated Total Cooling Capacity [W] will be limited by the maximum rated volume flow per rated total capacity ratio"

Adjusting the Sizing:Zone supply air temperature should change the zone air flow rate. It may be that the heating flow r

2019-04-18 08:20:47 -0500 commented answer VRF templates : How to fix these error: "Gross Rated Total Cooling Capacity [W] will be limited by the maximum rated volume flow per rated total capacity ratio"

Adjusting the Sizing:Zone supply air temperature should change the zone air flow rate. It may be that the heating flow r

2019-04-17 11:45:57 -0500 commented question VRF templates : How to fix these error: "Gross Rated Total Cooling Capacity [W] will be limited by the maximum rated volume flow per rated total capacity ratio"

@Alexis, did changing the SAT in the Sizing:Zone object help?

2019-04-17 11:41:37 -0500 commented answer VRF templates : How to fix these error: "Gross Rated Total Cooling Capacity [W] will be limited by the maximum rated volume flow per rated total capacity ratio"

From your table, the coils with the warnings have a higher supply air temperature with a requested capacity lower than t

2019-04-17 11:41:10 -0500 commented answer VRF templates : How to fix these error: "Gross Rated Total Cooling Capacity [W] will be limited by the maximum rated volume flow per rated total capacity ratio"

From you table, the coils with the warnings have a higher supply air temperature with a requested capacity lower than th

2019-04-17 11:06:29 -0500 answered a question How to keep air loop flow rate as the one imposed by schedule? and not automatically varied according to cooling load

You might try using the min/max schedules in the outdoor air controller to replicate your schedule. Use a fractional sch

2019-04-17 08:45:51 -0500 commented answer VRF templates : How to fix these error: "Gross Rated Total Cooling Capacity [W] will be limited by the maximum rated volume flow per rated total capacity ratio"

And I may have led you in the wrong direction. Zone air flow = Q/(Cp*deltaT) so as deltaT (Tzone - Tsupply air) increase

2019-04-17 08:42:57 -0500 commented answer VRF templates : How to fix these error: "Gross Rated Total Cooling Capacity [W] will be limited by the maximum rated volume flow per rated total capacity ratio"

So when you adjusted the Sizing:Zone supply air temperature did you see a change in the flow per capacity ratio in the w

2019-04-15 11:58:37 -0500 commented answer VRF templates : How to fix these error: "Gross Rated Total Cooling Capacity [W] will be limited by the maximum rated volume flow per rated total capacity ratio"

Did you try lowering the Sizing:Zone supply air temperature to increase the autosized zone air flow rate?

2019-04-15 11:56:11 -0500 commented answer How to determine custom chiller performance curves with correct coefficients?

The EIRFPLR curve is really a power output versus PLR curve. So this curve looks approximately proportional to PLR (e.g.

2019-04-15 11:49:02 -0500 commented answer Error while trying to output Zone People Occupant Count from energyplus

OK, your right. The "Zone People Occupant Count" is for the zone since there can be more than 1 People object per zone.

2019-04-05 07:15:28 -0500 answered a question VRF templates : How to fix these error: "Gross Rated Total Cooling Capacity [W] will be limited by the maximum rated volume flow per rated total capacity ratio"

I assume you are autosizing the coils otherwise you could have specified the correct flow ratio. In the Sizing:Zone obje

2019-04-04 08:00:09 -0500 commented answer Is Appendix G becoming irrelevant?

@luisclv, one question. Why is lighting based on occupancy one of the "aspects that are difficult to model accurately (l

2019-04-04 07:24:34 -0500 answered a question How Water Acummulation Tank in EnergyPlus

The water heaters can also be used as storage tanks. Both the WaterHeater:Mixed and WaterHeater:Stratified have 2 sets o

2019-04-02 07:29:24 -0500 commented answer Desiccant Wheel with both sides in the Supply Flow

For control of the desiccant wheel the availability schedule can turn off the HX when needed. If you want it to operate

2019-03-27 18:29:53 -0500 edited answer Severe errors in air loop....!

Water cooling coils are reverse action ... more flow = lower outlet temp. The warning shows the sensed (air) temp = 9.3

2019-03-27 18:28:11 -0500 answered a question Severe errors in air loop....!

Water cooling coils are reverse action ... more flow = lower outlet temp. The warning shows the sensed (air) temp = 9.3

2019-03-27 17:45:03 -0500 commented answer Severe errors in air loop....!

So why are you trying to control a water cooling coil as normal action (i.e., more water flow = higher outlet air temp)?

2019-03-27 08:52:55 -0500 commented answer Set Heating and Cooling availability schedule for Ideal load air system

I think you need to use HeaAvaActuator = 1 (or 0) in your EMS program.

2019-03-27 08:51:58 -0500 commented answer Set Heating and Cooling availability schedule for Ideal load air system

@mjwitte any thoughts?

2019-03-27 08:51:17 -0500 commented answer Set Heating and Cooling availability schedule for Ideal load air system

Oh wait. It is HeaAva, so I am also confused.