It is not necessary to simulate the DHW and HW at the same time. This is a simulation. Simulation need not be exactly as the real system. I have fill in some more comments on the chart. If you can fill in some temperature values, you will see that the fire is not controlled by the zone temperature or any fixed value. The boiler thermostat simply cycling on and off, during the day. You do not have simulate this part, which part do you mean? you mean the part that the fire is controlled by fixed value?
although it is very easy to do. could you please explani more about it ?how can i do it?
You simply let the boiler cool down by itself, the fire will cycle on and off. In your last IDF simulation, you already have the water flow rate through each radiator. This is the design maximum or the setting of the mannual valve of each radiator.This is how you use the simulation. Find the operating condition of a real system using simulation. When you do this you need not operate the DHW. If you do use DHW, the DHW water usage wil appear in the different part of the simulation. Forget about zone controlling the boiler or add more set point to control the boiler. You need to design this and find out exactly how the real system operates. You should not simply try to follow what you think you have in the real system. This is why I asked you to complete the schematic diagram.
If you think there is a thermostat controlling the HW pump, show it in the diagram and it can be simulated. If you want to change the boiler thermostat to a more precise one, it can be done. could you please say how i change the boiler thermostat to a more precise?
Then you must measure the outlet pipe temperature when the boiler is on and off. The difference in temperature between the outlet and the return (inlet) allows you to calculate the heat load, if the flow rate is known. What ever you use in the IDF is working. Low temperature radiant panel definitely will not work for you. Whether you call it a radiator or baseboard heater does not matter, if you think they looked different. The heat is still at the baseboard level. Both are by radiation and convection to provide heating. The real system DHW uses the same boiler. Off course it will turn on and off the boiler, b ecause it cools the boiler down when in use. yes
When the boiler is on, it does not know whether the heat is used by the DHW or HW. yes
In the simulation, the conditions are shown, and you can study the operation in more detail.
In EPlus simulation, the zone cools the water in the radiator. The return water temperature will lower the tank temperature. When this temperature reaches the low tank operating limit, the fire turns on. Thermostat is now in the ON position. When the tank temperature reaches the 80°C set point, the thermostat turns the fire off. How long it stay in the ON position depends on the size of the tank and the capacity of the heating source. sorry how cal i use tank for my boiler ? the boiler in this building has tank, and its tank has thermostat , and has deadband temperature , but i dont know how i can set tank for the boiler in energyplus?
When you choose autosize and not required to match a real system, you need not care about this part.
If you want to match the real equipment, you must make sure that the building section is correct. You cannot keep repeating what you have doing without mentioning the building. You have measured the follow rate, the boiler capacity, the radiator size, etc. Therefore, you going around in a circle.
because boiler in enregyplus controls with zone mean air temperate , but in my building the tank water of boiler switch off /on boiler ,
This is not a correct statement. The boiler in EPlus is not controlled by the zone mean air temperature. The radiators in EPlus cool down the boiler and then the fire comes on.If the radiators are off, the by-pass return is at the same temperature as the boiler. Therefore, the boiler never cools down. thanks for your good explanation i undrestand it well This is of cource not real in practice, and is compensated by other object fields in the IDF. could you please how i can show this by other object fields in the idf?
This is why every fields in an EPlus object must be read and understood.
the thermostat of boiler ( aquastat ) switch on/off the burner , and the thermostat surface on the main return pipe hot water loop that it controls hot water pump (HW pump ) and another thermostat on the domostic hot water pipe of coil tank for domostic hot water that controls when water of in the coil needs heat
I do not believe that this paragraph is correct, because these thermostats were not on the schematic diagram you have provided.
yes i complete it in the schematic diagram that i send the picture of the power house of this building , the boiler in my building has tank and so the tank has thermostat and also has deadband but i dont know how i can show this in energyplus?
thanks
You will not be able to use the set point managers and EMS, if you cannot distinguish a thermometer from a thermostat function.
i know what is different between thermostat and thermometer , thermometr just measured the temperature of that node , but themostat controls the temperature ,
You will have to show this in the schematic diagram.
Dr. Li
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
From: t.t111ir@xxxxxxxxxDate: Wed, 22 Feb 2012 13:38:22 +0000Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Wednesday, February 22, 2012 4:18 PM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
I am just pointing out to you there are such devices. Whether you have it or not, you have to find out. In an old system, the user control the valve to get the desired temperature in the room. ok but in energyplus when air temperature reaches thermostat setpoint temperature , boiler will be off , but in my building boiler wouldnt controlled by zone air temperature , outlet temperature controls boiler,
dr.li i find solution for my problem but i dont know is that right or not , instead of the using two loops , HW loop ( boiler + hw pump + source side indirect water heater +baseboard ) and DHW loop ( indirect water heater + DHW pump ) i can use HW loop ( water heater +hw pump + source side ondirect water heater +baseboard) and DHW loop (indirect water heater + DHW pump ), but i dont know , using water heater with base board in HW plant is correct or not ?
because boiler in enregyplus controls with zone mean air temperate , but in my building the tank water of boiler switch off /on boiler ,
There is no theremostat control for each room to contron the common system, apart from the possible local valve thermostat. (automatic or manual.)
Most of the air system do not have individual room thermostat either. The temperature is adjusted by fixed damper using the ADU:uncontrolled (Direct Air). AHU has one theremostat control from the master zone. yes i know about it
Dr. Li
To: EnergyPlus_Support@xxxxxxxxxxxxxxx From: t.t111ir@xxxxxxxxx Date: Wed, 22 Feb 2012 09:29:44 +0000 Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
Dr.Li , i think you think that my radiator in my system has thermostatic valve , but it doesnt have thermostatic valve , the plant controlled with water temperature , not zone air temperature
From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Tuesday, February 21, 2012 11:18 PM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
In that case, detach the DHW or assume that its working temperature can be ignored. You said that it has an auxiliary heater at one time. Control the pump with a zone theremostat, or set the boiler thermostat to what you want. Simple. Dr. Li
To: EnergyPlus_Support@xxxxxxxxxxxxxxx From: t.t111ir@xxxxxxxxx Date: Tue, 21 Feb 2012 19:20:39 +0000 Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
because the building that i want to simulate , it works according to controling plant temperature not zone air temperature ,
ok thanks
From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Tuesday, February 21, 2012 10:41 PM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
Go ahead and program what you wanted in the IDF and run it. It can be done. How? I do not think I want to spend any more time on email. As your earlier IDF was already running, I do not know why you keep wanting to control the plant temperature and ignoring the zone control and building errors. These numbers are in the plant sizing and boiler design. Of cource, you can use setpoint manager and EMS as well. Dr. Li
To: EnergyPlus_Support@xxxxxxxxxxxxxxx From: t.t111ir@xxxxxxxxx Date: Tue, 21 Feb 2012 19:03:15 +0000 Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Tuesday, February 21, 2012 10:15 PM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
Dr.Li :
in the building that i simulated :The real building or the IDF?
real building
the thermostat of boiler ( aquastat ) switch on/off the burner , and the thermostat surface on the main return pipe hot water loop that it controls hot water pump (HW pump ) and another thermostat on the domostic hot water pipe of coil tank for domostic hot water that controls when water of in the coil needs heat
If these are on your real building, they are thermometers, and do not do any controlling.
no there are nt thermometr , there are thermostat ,
thermometr just measured tempersture but thermostat conrols temperature,
If these are in the IDF, they should be properly entered with the correct names, controllers and managers. They are not necessary, as the boiler thermostat will do all these for you.
Dr.Li , what is boiler thermostat in energyplus ?is this design outlet water temperature in boiler class ? you mean when i enter design outler water temperature: 80 , it means when outlet boiler temperature is greater than 80 then boiler will be off and when less than 80 it will be on ?it doesn have any deadband?
You will not be able to use the set point managers and EMS, if you cannot distinguish a thermometer from a thermostat function.
i know what is different between thermostat and thermometer , thermometr just measured the temperature of that node , but themostat controls the temperature ,
I kept saying that you need not control the pump in the EPlus simulation, and you insist that it must stop at 80°C and start at 65°C and turn on and off the boiler fire. The system does not operate in your way.
i say
boiler will be on and off with its temperature of burner ( if greater than 8o boiler will be off , and if less than 75 will be on , 5 is its deadband) and i say hw pumo contrl with its own thermostat that install in the return hot water pipe ,
You e-mail below showed a DHW schedule which is on all the time except at 3am. That was why I said that your pump will not turn off. You have not proved that the schedule was actually working in your IDF.
yes i know that , in my schedule the domostic hot water for 3 am is 0 then DHW pump will be off , but i talk about hw pump controll
Showing me some isolated schedules and objects will not help.
Dr. Li
To: EnergyPlus_Support@xxxxxxxxxxxxxxx From: t.t111ir@xxxxxxxxx Date: Tue, 21 Feb 2012 15:05:54 +0000 Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Monday, February 20, 2012 9:51 PM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
An intermitent pump in EPlus is one which can be switched on and off. The pump itself does not sense the flow rate, the pressure or the temperature. It is switched on/off by another controller. could you please describe more little about what controller?
It may turn itself off, if the pressure is too high for safety reasons. This is why you have a by-pass branch in the loop. The thermostat turns off the burner.
the zone air thermostat turn off the burner? It should not turns off the pump at the same time, unless the pump has a by-pass. I do not know what switches it off in your real system.
Dr.Li : in the building that i simulated : the thermostat of boiler ( aquastat ) switch on/off the burner , and the thermostat surface on the main return pipe hot water loop that it controls hot water pump (HW pump ) and another thermostat on the domostic hot water pipe of coil tank for domostic hot water that controls when water of in the coil needs heat
Dr. Li
To: EnergyPlus_Support@xxxxxxxxxxxxxxx From: t.t111ir@xxxxxxxxx Date: Mon, 20 Feb 2012 18:11:21 +0000 Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
Dr.Li can you say what does intermitent pump in energyplus?
the pump will run at its capacity if a load is sensed and will shut off if there is no load on loop ,
can you explain it please ?
From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Monday, February 20, 2012 9:36 PM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
You have some input to the IDF for the DHW usage. I have no idea whether it is running or not in the simulation. Please do not show me a spread sheet for some measured results, and theb link my comments for the spread sheet to the simulation that I do not know. Dr. Li
To: EnergyPlus_Support@xxxxxxxxxxxxxxx From: t.t111ir@xxxxxxxxx Date: Mon, 20 Feb 2012 17:02:33 +0000 Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
Dear Dr.Li ,
i dont undrestandt you said i was not using the DHW,
i use :
Schedule:Compact,
Sinks Flow Schedule, !- Name
Any Number, !- Schedule Type Limits Name
THROUGH: 12/31, !- Field 1
FOR: AllDays, !- Field 2
UNTIL: 1:00, 0.003, !- Field 4
UNTIL: 2:00, 0.001, !- Field 6
UNTIL: 3:00, 0, !- Field 8
UNTIL: 4:00, 0, !- Field 10
UNTIL: 5:00, 0.001, !- Field 12
UNTIL: 6:00,
0.028, !- Field 14
UNTIL: 7:00, 0.105, !- Field 16
UNTIL: 8:00, 0.1, !- Field 18
UNTIL: 9:00, 0.081, !- Field 20
UNTIL: 10:00, 0.059, !- Field 22
UNTIL: 11:00, 0.051, !- Field 24
UNTIL: 12:00, 0.037, !- Field 26
UNTIL: 13:00, 0.031, !- Field 28
UNTIL: 14:00, 0.026, !- Field 30
UNTIL: 15:00, 0.023, !- Field 32
UNTIL: 16:00, 0.033, !- Field 34
UNTIL: 17:00, 0.041, !- Field 36
UNTIL: 18:00, 0.063, !- Field 38
UNTIL: 19:00, 0.075, !- Field 40
UNTIL: 20:00, 0.066, !- Field 42
UNTIL: 21:00, 0.059, !- Field 44
UNTIL: 22:00, 0.046, !- Field 46
UNTIL: 23:00, 0.046, !- Field 48
UNTIL: 24:00, 0.025; !- Field 50
=========== ALL OBJECTS IN CLASS: WATERUSE:EQUIPMENT ===========
WaterUse:Equipment,
Sinks, !- Name
Sinks, !- End-Use Subcategory
0.000158, !- Peak Flow Rate {m3/s}
Sinks Flow Schedule, !- Flow Rate Fraction Schedule Name
Sinks and Showers Temp Schedule; !- Target Temperature Schedule Name
!- =========== ALL OBJECTS IN CLASS: WATERUSE:CONNECTIONS ===========
WaterUse:Connections, Domestic Hot Water, !- Name Domestic Hot Water Inlet Node, !- Inlet Node Name Domestic Hot Water Outlet Node, !- Outlet Node Name , !- Supply Water Storage Tank Name , !- Reclamation Water Storage Tank Name , !- Hot Water Supply Temperature Schedule Name
, !- Cold Water Supply Temperature Schedule Name NONE, !- Drain Water Heat Exchanger Type , !- Drain Water Heat Exchanger Destination , !- Drain Water Heat Exchanger U-Factor Times Area {W/K} Sinks; !- Water Use Equipment 1 Name
Schedule:Compact,
Sinks and Showers Temp Schedule, !- Name
Any Number, !- Schedule Type Limits Name
THROUGH: 12/31, !- Field 1
FOR: AllDays, !- Field 2
UNTIL: 24:00, 40.56; !- Field 4
with this input i think i used DHW , and also i put :
PlantEquipmentOperation:HeatingLoad,
DHW Control Scheme, !- Name
0, !- Load Range 1 Lower Limit {W}
90000, !- Load Range 1 Upper Limit {W}
DHW Plant Equipment; !- Range 1 Equipment List Name
PlantEquipmentOperation:HeatingLoad,
Central Boiler Only, !- Name
0, !- Load Range 1 Lower Limit {W}
90000, !- Load Range 1 Upper Limit {W}
heating plant; !- Range 1 Equipment List Name
Dr.Li can you say what does intermitent pump in energyplus?
the pump will run at its capacity if a load is sensed and will shut off if there is no load on loop ,
can you explain it please ?
From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Monday, February 20, 2012 7:09 PM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
That was because you were not using the DHW, and you have 1 mega watt of furnace power. The boiler furnace does not control the HW pump. Dr. Li
To: EnergyPlus_Support@xxxxxxxxxxxxxxx From: t.t111ir@xxxxxxxxx Date: Mon, 20 Feb 2012 13:47:43 +0000 Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
it is my experiment data , and i have HW pump off and boiler on
but in my result energyplus i dont have this state , HW pump never off
From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Monday, February 20, 2012 4:38 PM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
All four states are on the spread sheet. Sorry. I means row 11 an row 12 of the spread sheet.. The year was 2010. Was it that long ago? Dr. Li
Boiler HW pump (Starting on row 9)
| 1 |
1 |
| 1 |
1 |
| 1 |
0 |
| 1 |
0 |
| 0 |
0
You missed out this state.
|
| 0 |
1 |
| 0 |
1 |
| 1 |
1 |
| 0 |
1 |
| 0 |
1 |
| 1 |
1 |
| 0 |
1 |
| 1 |
1 |
| 0 |
0 |
| 0 |
0 |
| 1 |
0 |
| 1 |
0 |
To: EnergyPlus_Support@xxxxxxxxxxxxxxx From: t.t111ir@xxxxxxxxx Date: Mon, 20 Feb 2012 00:41:02 +0000 Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
excuse me i dont undrestand : on line 11 and 12 " what you mean ?
now in iran is 4:10 AM
From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Monday, February 20, 2012 4:06 AM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
On line 11 and 12. and more later on. Dr. Li
To: EnergyPlus_Support@xxxxxxxxxxxxxxx From: t.t111ir@xxxxxxxxx Date: Mon, 20 Feb 2012 00:32:04 +0000 Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
Dr.Li sorry for my mistake i dont see the result of HW pump off and boiler on ,
i dont undrestand why , ?
From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Monday, February 20, 2012 3:55 AM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
This is why you must not change names and create different names of the objects. "HW pump" is not the same as "pump" to me. I do not associate 3 and 4 with the spread sheet as they are only for two other variables. HW pump on and boiler off is a valid state, because the pump is not controlled by the boiler. The pump is on the supply side water loop, the boiler fire is on the heating tank source side, and is not in the water loop. Your statement on EPlus is not correct. Dr. Li
To: EnergyPlus_Support@xxxxxxxxxxxxxxx From: t.t111ir@xxxxxxxxx Date: Sun, 19 Feb 2012 23:57:37 +0000 Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
From: YuanLu Li <yli006@xxxxxxxxxxx>
To: EnergyPlus_Support <energyplus_support@xxxxxxxxxxxxxxx>
Sent: Monday, February 20, 2012 3:14 AM
Subject: RE: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
thanks for looking that
The data looked normal. You should have taken the temperature values at the same time. yes i take it but in the excel file that i send you there is nt,
You did not record the DHW pump on the spread sheet.
i recorded DHW pump , but in this file that i send you it is only HW pump HW pump off, boiler off not listed below,
i wrote wrong in number 3, sorry , it must be HW pump off ,boiler off there is on the spread sheet.
in my energyplus result i dont see number 4 case (HW pump on and boiler off ) i dont undrestand why?
) Hw pump off but boiler on (DHW is being heated)
2)Hw pump on and boiler on (Normal )
3)HW pump 0ff but boiler on (HW below set point, DHW not in use)
4)HW pump on and boiler off (Tank is hot enough for a while) i dont this case result ( HW pump on and boiler off ) in my energyplus result ,
This is an indication that you did not plan the experiment well, and do not record the actual condition on site. Instead of 0 and 1's on the spread sheet, you should combined the states and then list the meaning of each state. Two pumps and a boiler fire should give you 8 states.
yes you are right i have 8 states, but in the excel file that i sent you , there is only the result of HW pump and boiler
Some states may not be possible, and then your should try to explain them. Dr. Li
To: EnergyPlus_Support@xxxxxxxxxxxxxxx From: t.t111ir@xxxxxxxxx Date: Sun, 19 Feb 2012 21:58:35 +0000 Subject: Re: [EnergyPlus_Support] availabilityManager:High temperaturTurnoff
please see the file that i attached :this is the real experiment data that i measured :
it shows some times all of below
1) Hw pump off but boiler on (DHW is being heated)
2)Hw pump on and boiler on (Normal )
3)pump 0ff but boiler on (HW below set point, DHW not in use)
4)pump on and boiler off (Tank is hot enough for a while)