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[EnergyPlus_Support] Re: availabilityManager:High temperaturTurnoff





Dear Dr.Li

I'm sorry to butt into your conversation.

If those systems ( VAV VRV HVAC system) are not energy efficient, could you please let me know what kind of system is energy efficient? 

(Something like, radiant heating systems or FCUs which delivery the heat source to the room directly ?)

Thanks in advance

best regards

Kim


--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, YuanLu Li <yli006@...> wrote:
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> 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@...
> Date: Fri, 27 Jan 2012 22:09:44 +0000
> Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
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> yes exactly we use pump by bypass mode . what do you mean by different algorithm?
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> From: YuanLu Li yli006@...
> To: EnergyPlus_Support energyplus_support@xxxxxxxxxxxxxxx
> Sent: Friday, January 27, 2012 10:24 PM
> Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
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> If you turn on and off the pump at 65°C, to implement the pump by pass mode. Again, it is a different algorithm.
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> Dr. Li
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> To: EnergyPlus_Support@xxxxxxxxxxxxxxx
> From: t.t111ir@...
> Date: Fri, 27 Jan 2012 18:43:08 +0000
> Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
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> i want to :
> if inlet water pump > 65C then pump will be off
> and if inlet water pump < 65 then pump will be on
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> for this type of controling can we use two availabilityManager:
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> 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
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> From: Richard Raustad RRaustad@...
> To: EnergyPlus_Support@xxxxxxxxxxxxxxx
> Sent: Friday, January 27, 2012 8:12 PM
> Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
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> The availability manager actually turns off the pump (or fan for air systems). So any equipment on that loop will be off.
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> On 1/27/2012 11:25 AM, Tooran T wrote:
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> From: YuanLu Li yli006@...
> To: EnergyPlus_Support energyplus_support@xxxxxxxxxxxxxxx
> Sent: Friday, January 27, 2012 7:31 PM
> Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
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> 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?
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> thank you very much Dr.Li
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> !- =============
> 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
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> To: energyplus_support@xxxxxxxxxxxxxxx
> From: yli006@...
> Date: Fri, 27 Jan 2012 08:21:27 -0500
> Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
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> If the avilability manager is associated with the heater, it turns off the heater.
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> If the avilability manager is asspcoated with the tank used side, it turns off the loop supply (pump).
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> 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.
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> Dr. Li
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> To: EnergyPlus_Support@xxxxxxxxxxxxxxx
> From: t.t111ir@...
> Date: Fri, 27 Jan 2012 09:36:16 +0000
> Subject: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
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> 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."
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> 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.
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> then availabilityManager:High temperaturTurnoff turn off boiler or plant loop ?if it turn off the plant loop it means it turned off pump too?
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> thanks
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> --
> Richard A. Raustad
> Senior Research Engineer
> Florida Solar Energy Center
> University of Central Florida
> 1679 Clearlake Road
> Cocoa, FL 32922-5703
> Phone: (321) 638-1454
> Fax: (321) 638-1439 or 1010
> Visit our web site at: http://www.fsec.ucf.edu
>
> UCF - From Promise to Prominence: Celebrating 40 Years
>


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