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2019-03-21 11:06:56 -0500 commented answer how to control DOAS supply fan and damper?

Are you trying to set up a 100% outdoor air system?

2019-03-21 10:37:12 -0500 commented answer how to control DOAS supply fan and damper?

Your DOAS (really an air loop with an outside air system) outlet temperature = constant 26C which enters the VAV boxes.T

2019-03-20 13:28:51 -0500 commented answer how to control DOAS supply fan and damper?

click on my name for email address

2019-03-20 10:05:10 -0500 commented answer how to control DOAS supply fan and damper?

There are 2 types of systems, an outdoor air system (to meet the OA need) and a recirculation system (to meet the load).

2019-03-19 11:42:05 -0500 answered a question how to control DOAS supply fan and damper?

The fan does not control the flow, it reacts to flow. Other objects control flow such as the air terminals as you descri

2019-03-19 09:13:50 -0500 commented answer VRF with AHU in Design Builder. Replacing DX Coil curves with VRF.

The VRF terminal units in EnergyPlus are controlled by zone load. I don't think you can put a VRF TU in an outdoor unit

2019-03-14 14:06:13 -0500 answered a question Heat Exchanger with autosized flow rate generates warning about flow rate

When the HX is in the outdoor air system and the air loop operates at a flow rate less than the autosized outdoor air fl

2019-03-14 12:44:33 -0500 commented answer Coil, Fan and VRF Terminal not Operating Continuously on VRF System

For the cooling coil described here (347), the TU with this coil is on a VRF system that has 35 other TUs attached. I am

2019-03-14 12:03:48 -0500 commented answer Bypass of HeatExchanger:AirToAir:SensibleAndLatent based on temperature

Another thought is to set up an OA economizer. From the IO Ref for this HX: When an air-side economizer is also being mo

2019-03-14 08:49:39 -0500 answered a question Bypass of HeatExchanger:AirToAir:SensibleAndLatent based on temperature

It sounds as if you have tried all the options available and it works at times while not working at other times. You nee

2019-03-14 07:39:40 -0500 answered a question VRF with AHU in Design Builder. Replacing DX Coil curves with VRF.

VRF terminal units can be connected to a DOAS using the AirTerminal:SingleDuct:Mixer object. See the EnergyPlus example

2019-03-13 11:56:13 -0500 commented answer Coil, Fan and VRF Terminal not Operating Continuously on VRF System

Seems like it should be working on the weekends. I think at this point I would need to see your E+ input file or send yo

2019-03-13 11:01:00 -0500 answered a question Coil, Fan and VRF Terminal not Operating Continuously on VRF System

Interesting runtime fraction plot (Picture 10). The cooling coil total cooling rate and cooling coil runtime fraction wo

2019-03-06 15:29:24 -0500 commented answer Outside air flow rate is not constant for WSHP OS

The way E+ models the on off fan is to calculate a part load ratio (PLR is a fraction from 0 to 1) for each time step. T

2019-03-06 15:26:57 -0500 commented answer Outside air flow rate is not constant for WSHP OS

The way E+ models the on off fan is to calculate a part load ratio (PLR is a fraction from 0 to 1) for each time step. T

2019-03-06 11:26:37 -0500 commented answer Access tomorrow's weather data using EMS

I understand. That's the only suggestion I can think of at this time.

2019-03-06 11:18:24 -0500 edited answer Outside air flow rate is not constant for WSHP OS

The ZoneHVAC:WaterToAirHeatPump has an input field that allows a schedule to be used to control the fan operation. If th

2019-03-06 11:17:22 -0500 commented question Outside air flow rate is not constant for WSHP OS

In EnergyPlus a cycling fan cycles based on load each time step. This is analogous to the AC system in your home operati

2019-03-06 11:15:29 -0500 answered a question Outside air flow rate is not constant for WSHP OS

The ZoneHVAC:WaterToAirHeatPump has an input field that allows a schedule to be used to control the fan operation. If th

2019-03-06 11:11:13 -0500 answered a question Access tomorrow's weather data using EMS

You could use a day ahead weather file schedule and access that schedule via EMS.

2019-03-06 09:45:15 -0500 commented question Outside air flow rate is not constant for WSHP OS

It appears that the WSHP is cycling to meet the load which will vary the air flow rate during each time step. What is th

2019-03-05 14:15:42 -0500 answered a question please someone should help me out with this error input file

From the warning, Construction object with name = Construction 1 has a missing required input for field outside layer.

2019-03-05 08:25:29 -0500 commented question Outside air flow rate is not constant for WSHP OS

OA can only flow through the WSHP when the WSHP fan is on. You need to check OA flow at the inlet to each WSHP to see mo

2019-03-05 08:24:32 -0500 commented question Outside air flow rate is not constant for WSHP OS

OA can only flow through the WSHP when the WSHP fan is on. You need to check OA flow at the inlet to each WSHP to see mo

2019-03-05 07:33:06 -0500 answered a question How to set the leaving and entering water temperature of water-to-water heat pump in energyplus

The leaving water temperature is set in the plant using a SetpointManager:* object. Place a set point manager at the out

2019-03-04 12:52:07 -0500 commented question BEopt electric furnace strange behavior

There must be another heating source if the zone temp remains unchanged. Or a bug where the electric heater sill provide

2019-02-28 23:02:33 -0500 answered a question What could be the reason why terminal unit reduce cooling even though the zone cannot meet setpoint?

This is extremely interesting from a VAV model perspective. The terminal unit does not have a cooling capacity per say,

2019-02-28 13:10:17 -0500 answered a question Why cooling loads appear during the cold months ? Heating/Cooling loads using E+

The winter building loads are impacted by the under-slab ground temperatures and whether or not the simulation considers

2019-02-28 07:46:15 -0500 answered a question How can i solve the warning about water-to-water heat pump

The warnings show that the water temperature is -10.99 C. This is obviously wrong and something in the simulation is cau

2019-02-27 22:49:40 -0500 answered a question CAV system water coil controller Energy plus

A water coil is controlled by specifying a set point at the coil air outlet node. There are many types of SetpointManage

2019-02-27 22:36:35 -0500 answered a question How to control the outcome of Chiller IPLV, so that it is as desired?

I understand that iterations would be necessary to adjust results of a simulation. The chiller IPLV can be changed by ad

2019-02-27 13:16:33 -0500 answered a question Fan coil unit parameters simulation problem.

You have specified the coil rated parameters before you know what the actual coil load or entering air conditions are. I

2019-02-27 13:01:14 -0500 answered a question chiller performance curves

The performance curves in EnergyPlus define the performance of a specific model. In the case of chillers, the performanc

2019-02-26 07:33:39 -0500 answered a question Why am I reaching high temperature in the evening?

This usually means the HVAC system has been schedule off. Check the availability schedules on the HVAC system, coils, an

2019-02-25 18:49:29 -0500 commented answer how to autosize for dehumidification load in EnergyPlus

Not at this time.

2019-02-22 21:03:18 -0500 commented answer Water heater consumption (kWh)

You have 111 kWh's for Jan (domestic HW only I assume). I have measured my house and see about 3 kWh/day on water heatin

2019-02-22 20:56:05 -0500 commented answer Water heater consumption (kWh)

You have 111 kWh's for Jan (domestic HW only I assume).That's about 13 dollar electric bill in the US. This seems about

2019-02-22 20:55:11 -0500 commented answer Water heater consumption (kWh)

You have 111 kWh's for Jan (domestic HW only I assume).That's about /$13 electric bill in the US. This seems about right

2019-02-22 20:54:47 -0500 commented answer Water heater consumption (kWh)

You have 111 kWh's for Jan (domestic HW only I assume).That's about \/$13 electric bill in the US. This seems about righ

2019-02-22 20:54:25 -0500 commented answer Water heater consumption (kWh)

You have 111 kWh's for Jan (domestic HW only I assume).That's about a\/$13 electric bill in the US. This seems about rig

2019-02-22 20:53:11 -0500 commented answer Water heater consumption (kWh)

You have 111 kWh's for Jan (domestic HW only I assume).That's about a\/$13 electric bill in the US. This seems about rig

2019-02-22 20:52:50 -0500 commented answer Water heater consumption (kWh)

You have 111 kWh's for Jan (domestic HW only I assume).That's about a /$13 electric bill in the US. This seems about rig

2019-02-22 20:51:55 -0500 commented answer Water heater consumption (kWh)

You have 111 kWh's for Jan (domestic HW only I assume).That's about a $13 electric bill in the US. This seems about righ

2019-02-22 20:30:06 -0500 commented answer Water heater consumption (kWh)

I was comparing the 130 kWh to my own residential HW energy use (I've measured). About 3 kWh/day or 90 ish kWh/month. Th

2019-02-22 20:04:27 -0500 commented answer Water heater consumption (kWh)

Good, you have nearly zero'd the losses. Why is not 0?

2019-02-22 20:03:16 -0500 commented answer Water heater consumption (kWh)

Something is wrong. You have a 6 kW water heater with a 130898 W demand for January. We have to figure out what that mea

2019-02-22 19:52:16 -0500 edited question Water heater consumption (kWh)

Water heater consumption (kWh) Hi, I'm trying to simulate a stratified water heater for São Paulo-Brazil .epw and find o

2019-02-22 19:49:06 -0500 edited answer Water heater consumption (kWh)

You have what appears to be a large loss coefficient. WaterHeater:Stratified, Storage Tank Stratified, !- Name

2019-02-22 19:27:04 -0500 commented answer Water heater consumption (kWh)

Can you clean up that table in your description so I can see it better? The losses are about an order of magnitude lower

2019-02-22 19:26:00 -0500 commented answer Water heater consumption (kWh)

Can you clean up that table in your description so I can see it better? The losses are about an order of magnitude lower