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RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff





 

 

" The baseboard heater should be linked to the zone thermostat" and " verify that they are controlling the baseboard heater "

When you place a zone equipment into a zone, it is automatically linked to the zone thermostat.  When you use a template or schedule, the same temperature may be set for all the heaters.  One heating setpoint for all the zones. In each zone or zone  equipment there is a feild for schedule name for temperature setpoint.  By adding a prefix to this type of schedule, then each zone will use its own schedule.

 

In a real system, there is heat loss in the pipes, etc.  Depending on how the pipes are installe, the resistance to water flow is also different.   These can be simulated in EPlus, by providing more details, and not to use autosize.

 

It is not simple to accurately to simulate a real system.  Right now, the simulation is using the heating requirement and converting it to the water flow rate and temperature between the inlet and outlet of the radiator, which is also the water tank temperature.  The tank is maintained at a fixed temperature, with large heating source capacity.

 

Real simulation should not use autosizing.

=================

The  (FTFFF) can be ignored for the time being.  After cleaning up the schedules they may disappear.

 

"i dont have any cooling equipment , but i dont use cooling setpoint i use heating setpoint ( in zonecontrol:thermostat and control type is 1-thermostatsetpoint:singleheating.)"

 

Type4 and type2 are still in the IDF, I think.

=====================

Type4 thermostate, economizer mode,  and zoneventilation:Designflowrate can be scheduled to different flow rate at different outdoor temprature or season.

 

 Dr. Li  

 


To: EnergyPlus_Support@xxxxxxxxxxxxxxx
From: t.t111ir@xxxxxxxxx
Date: Fri, 3 Feb 2012 19:23:47 +0000
Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff

 
Dear Dr.Li ,
 
Thank you from your kindness and replying to my questions
I  Changebuilding ground temperature to 18°C for Tehran , and the warning eror  ".Site:GroundTemperature:BuildingSurface: Some values fall outside the range of 15-25C " disappear .
 
You say,  i can add ventilation in Summer without adding air-conditioners.  Ventilation would remove moisture as well.
yes you r right but i just want to simulate it during winter , and aslo in idf file i put :zoneventilation:Designflowrate .
 
 
You say ,i  have 130 FTFFF warnings.  6 x 24 = 144 timesteps for one day.  I did not check whether you have by-pass branches installed in the plant loop or not.  Without the by-pass branch the flow quantity can goes to zero.  Since you only have zone equipment, it is passed.  The plant should pass as well, if the flow is not zero.
 
yes you r right i didnt have bypass branches intalled in the plant loop , now i put branch by-pass in my idef , but still there is FTFFF warnings.
You do not have any cooling equipment, the the cooling load for all the zones is zero.  The cool setpoint for the zone thermostat may have caused this warning
yes i dont have any cooling equipment , but i dont use cooling setpoint i use heating setpoint ( in zonecontrol:thermostat and control type is 1-thermostatsetpoint:singleheating.)
 
The heating setpoint is the zone thermostat value.  The baseboard heater should be linked to the zone thermostat.  You can provide different setpoint schedule for each zone to verify that they are controlling the baseboard heater.
how i could verify they are controlling the baseboard heater ?
 as you say:.
 
In a real system, the radiator temperature are all different, and the boiler temperature is also not constant.  You may leave the radiator valve rully open and adjust the boiler temperature, so that the occupants have no control of the system temperature.  This is the most practical way.
 ,i leave the radiator valve rully open and adjust the boiler temperature, so that the occupants have no control of the system temperature.
  so i set the avarage of data zone temperature that i measured for whole two month of january and febuary, as heating setpoint .  baseboard dont controll by this temperature ,  , i mean the heat of baseboard cause this temperature .
so why you say  " The baseboard heater should be linked to the zone thermostat" and "  verify that they are controlling the baseboard heater " ?
 
i attached  the picture of this building
thankyou very much

From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Friday, February 3, 2012 4:47 AM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff

 
You have a large building to model.  On the whole the warning on non-convex surfaces may be ignored.
 
The error file and the edited IDF file is attached.  I removed about 300 of your meter variables.  From the temperature output and schedule values, your equipment and plant seems to be normal. 
 
I did not change the building ground temperature.  It is still at 14°C.
 
I think, you can add ventilation in Summer without adding air-conditioners.  Ventilation would remove moisture as well.
 
You have 130 FTFFF warnings.  6 x 24 = 144 timesteps for one day.  I did not check whether you have by-pass branches installed in the plant loop or not.  Without the by-pass branch the flow quantity can goes to zero.  Since you only have zone equipment, it is passed.  The plant should pass as well, if the flow is not zero.
 
You do not have any cooling equipment, the the cooling load for all the zones is zero.  The cool setpoint for the zone thermostat may have caused this warning.
 
The heating setpoint is the zone thermostat value.  The baseboard heater should be linked to the zone thermostat.  You can provide different setpoint schedule for each zone to verify that they are controlling the baseboard heater.
 
I have not checked the IDF after the sorting.  It was not easy to see the objects in the unsorted form.  I did not know how the building looks like, until I have run this first simulation.
 
However, I still do not know where these zones are in the building.  Block1 and Block7 are cooler being the ground floor and roof top, I assume.
 
 
 
 Dr. Li  

 
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
From: t.t111ir@xxxxxxxxx
Date: Thu, 2 Feb 2012 08:37:20 +0000
Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff

 

Dear Dr.Li,
 
i tried to write my IDF ,
there is some warning
1.SimHVAC: Maximum iterations (20) exceeded for all HVAC loops, at HCA, 01/21 00:00 - 00:06
   **   ~~~   ** SimFlags=[FTFFF] AirLoops[F],ZoneEq[T],NonZoneEq[F],PlantLoops[F],ElecCircuits[F]..F=ok,T=fail.
it has this warning for 14 timestep ,
2.Site:GroundTemperature:BuildingSurface: Some values fall outside the range of 15-25C.
 
and also in this building there is no cooling system so get this warning :
3-Calculated design cooling load for zone=BLOCK2:HALLW is zero
 
 i dont knowand could i ignor this warnings or not could you see it please ?
 
but i have  question :
1- as you say radiators in this building have manual valve setting ,  a valve that opens or closes to control the hot water flow ,  but   you said   The zone thermostat will be use to simulate the manual valve setting. could you please desribe it  more please?
in my expreience this mahual valve in winter season always fully open , i measured the zone air temperature at five minutes interval in for two month  jaunuary and february .
 you mean i enterd this data as zone thermostat temperature?
 
 
thanks
 
 

From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Saturday, January 28, 2012 11:27 PM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff

 
You should complete the building first and see how much you can simply, simply by hand scatching.
 
Then reduce the number of zones to a minimum to meet you observation requirement.
You can have a building of many zones, but only cool or heat a few zones.
 
The exterior envolope is important, but need not have small detales of in and out a few inches, so long the total floor and wall are the same.
 
In DesignBuilding I do not know whether you can verify the building without the other entries.  With IDF, you can without the schedules, and HVAC system and plants.
 
Then you add the templates.   Thermostat would be for the radiators.  Boiler for the plant.
Radiator is the same hot water  baseboard.   Use type4 for thermostat control types, and use two set point schedules with dead band.  Keep the zone name simple and short, so that it will be very long on the spread sheet header and graphs.
 
The building heat transfer property will tell you how much energy to heat. and cool.  You cannot degign the capacity from the boiler temperatue.

 Dr. Li  

 
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
From: t.t111ir@xxxxxxxxx
Date: Sat, 28 Jan 2012 19:45:35 +0000
Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff

 
yes you r right , that idef that i sent it is not my real building it so examination and learing to how set branch , i study and make it right and send my exact idef to you ,
 
thank you very much

From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Saturday, January 28, 2012 11:03 PM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff

 
I tried your IDF which was extracted from your hotmail.
 
The sorted file, the .csv and the error files are attached.  As you are using DesignBuilder or some other third party software, the warnings are expected.
 
You have a simple one zone building. The result showed that the coooling and heating are not properly applied.  The location seems to be in London, England.   The simulation was done without the weather file.
 
1)  If the building is not accurate in construction, the reasult will be meaning less.  Is it a simple one storey rectangular building with no partitions?  Where are the radiators, and plant rooms?
 
2)  The windows and doors shuld be in actual position, facing the correct orientation for solar radiation calculation.  Blinds should be specified, if used.
 
3)  Ceiling insulatin and roof design are important.  I do not think, it is flat.
 
4)  Schedules many not be correct.  for turning on the system and the lights, etc.  You also have mixed long and compact formats.
 
5)  No domestic hot water usuage in the simulation.  Two boilers may not give you savings.
 
Each warning in the error file would give you something to think about.
 
It is common for DesignBuider to provide unavailaable and un-necessary output variable request.  Over one hundred were selected.   DesignDay simulation does not give you monthly and annual values, and I usually do not use them as they do not provide information at the debugging state.
 
===============
When you do a simulation, you must have a plan in your own or plain language.
 
Occupancy:  Peple  number, period of day present. etc.  Who are these people.
Some would move in and out, some may be permanent in the building.
 
When to turn on the lights and equipment.  These can be verified with schedule value in the .csv.
 
Natural temperature output , add some venilation, to verify the building construction.
 
System node temperature to verify the equipment operaton.
 
===============
Use the .rdd file to select the report variable entries.  Make all the display in timestep.
 
No need to run the weather file, until you have sorted out what to include in the IDF.
 
=====================
When you have many radiators with a valve, it is like the diffusers with a damper.
 
Because they are all in one room, you can use just one radiator.  The zone thermostat will be use to simulate the manual valve setting.
 
The circulating pump is set very high. You can reduce it later to see the effect.  Boiler is not set to operate between 82 and 72°C.  I have not yet look at the system node values.  The availability manager and the schedules may lock the system out.
 
There is no cooling and exter ventilation in Summer.  Winter sun is turned off by cloud.
 
======================
YOu need to learn to find all these by reading the .csv file and turning on the diagnostics.
 

 Dr. Li  

 
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
From: t.t111ir@xxxxxxxxx
Date: Sat, 28 Jan 2012 13:33:53 +0000
Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff

 
Dear Dr.Li ,
 I m master of science mechanical engineering, and it is my project to simulate one building that my profesor show me , i do  experimental on that building  , and in my project i must simulate it and then i suggest some good saving energy method , in this building there is one boiler for hot water radiator and domostic hot water  , one
 way that i suggest that there is two boiler for this two aim one is for domostic hot water and another is for hot water  that result to saving energy , by the way im female not male .
 Dear Dr.Li as exactly you say 
You do not see or use a thermostat in the room, it is because the user is the termostat.
 
There is manual valve on the radiator.  Some of them are calibrated in temperature or just an marker.  The occupant will adjust that to suit their comfort.
  i dont use VAV HVAC System ,
 In the real system, the pump by-pass has a non return valve.  When the pump is working the pipe is closed.  When the return water temperature falls to below the set point, the pump is stopped, and the water flows through the by-pass.
 and exactly it is my system .  in this building for example in summer because outside weather is hot for saving energy the don use pump , the get out pump amn use bypass.
i think in energyplus i cant use bypass with supply pump.
 
you mean when there is no thermostat how i must enter in thermostat heating setpoint in energyplus ?
in my building this radiator in room with out thermostat
 
 
very very vry special thanks
From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Saturday, January 28, 2012 4:18 PM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff

 
There are many components in an old system that is very efficient.
 
You do not see or use a thermostat in the room, it is because the user is the termostat.
 
There is manual valve on the radiator.  Some of them are calibrated in temperature or just an marker.  The occupant will adjust that to suit their comfort.
 
I do not know why we talk about energy saving and yet want to throw away all the cost saving system.
 
There is no need to have VAV VRV HVAC system.  Most of them are not energy efficient.
 
I now understand why most new users are using the VAV tmplate and VAV zone equipment, because that was in the Gertting Started exercise.
===============================
For T.T's IDF, you can remove the first two objects on availabilityManager:..   .  They will not work as you intended.
 
Have a closer look at your Iran system.  You may be still missing some good features.
 
In the real system, the pump by-pass has a non return valve.  When the pump is working the pipe is closed.  When the return water temperature falls to below the set point, the pump is stopped, and the water flows through the by-pass.
 
In the London furnace, there is a safety valve with steam whistle.  The water temperature is controlled by chimney damper setting and the fire air inlet size.  Again, there was no thermostat.  When the temperature is too high, all occupants would notice and would go to the furnace to shut it down, or call the attendant.
 
No thermostat, does not mean that there is no control.
 
Dr. Li.


 Dr. Li  

 
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
From: t.t111ir@xxxxxxxxx
Date: Fri, 27 Jan 2012 22:09:44 +0000
Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff

 
yes exactly we use pump by bypass mode . what do you mean by different algorithm?

From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Friday, January 27, 2012 10:24 PM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff

 
If you turn on and off the pump at 65°C, to implement the pump by pass mode.  Again, it is a different algorithm.

 Dr. Li  

 
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
From: t.t111ir@xxxxxxxxx
Date: Fri, 27 Jan 2012 18:43:08 +0000
Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff

 
i want to :
if inlet water pump > 65C then pump will be off
and if inlet water pump < 65 then pump will be on
 
for this type of controling can we use two availabilityManager:
 
one availabilityManager:High temperaturTurnoff  :for  inlet water pump > 65C then pump will be off .
and another availabilityManager: low temperaturTurnon : for inlet water pump < 65 then pump will be on.
is that right?
thanks
 
 
From: Richard Raustad <RRaustad@xxxxxxxxxxxx>
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
Sent: Friday, January 27, 2012 8:12 PM
Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff

 
The availability manager actually turns off the pump (or fan for air systems). So any equipment on that loop will be off.

On 1/27/2012 11:25 AM, Tooran T wrote:
 


From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Friday, January 27, 2012 7:31 PM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff

  thanks Dr.Li ,
i m not good at english so mybye i dont undrestand your word exactly  .you say : "  If the avilability manager is associated with the heater, it turns off the heater." and
" The size and type of the heater is another matter" what you mean by heater ?is that baseboard heater or water heater?
 
thank you very much Dr.Li
!- =============
  Sizing:Plant,
Boiler  Loop, !- Plant or Condenser Loop Name
HEATING, !- Loop Type
80., !- Design Loop Exit Temperature {C}
15; !- Loop Design Temperature Difference {deltaC}
!- ======================
 
is all you need to enter in the IDF.  The size and type of the heater is another matter.
=============================
In control engineering most controller has a built in hysteresis.  However, you may not be able to specify it exactly, if it is not designed to be adjustable. 
 
What you are trying to do is to design your own controller.
 Dr. Li  

 
To: energyplus_support@xxxxxxxxxxxxxxx
From: yli006@xxxxxxxxxxx
Date: Fri, 27 Jan 2012 08:21:27 -0500
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff

 
If the avilability manager is associated with the heater, it turns off the heater.
 
If the avilability manager is asspcoated with the tank used side, it turns off the loop supply (pump).
 
Sensor node need not be in the same loop, but must respond of the change when the control is activated.  If the temperature falls below the limit, the control is removed.  Back to your thermostat problem.   Set-back is not the same as  limits.

 Dr. Li  

 
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
From: t.t111ir@xxxxxxxxx
Date: Fri, 27 Jan 2012 09:36:16 +0000
Subject: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff

 
Dear memebers ,
ref : Document :EngineeringRefrence.pdf -983
"High temperature turn off :
The input object availabilityManager:High temperaturTurnoff is used to turn off a central air system or a plant loop if a sensed node temperature exceeds a temperature limit."

i want to know availabilityManager:High temperaturTurnoff , turn off the plant loop or just the turn off the component ?
for example : i set field :Sensor Node name : at the outlet of boiler .. in this plant loop there is pump and boiler as a component.

then availabilityManager:High temperaturTurnoff turn off boiler or plant loop ?if it turn off the plant loop it means it turned off pump too?

thanks






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