Re: [EnergyPlus_Support] G3.1.3.11

Hum, I just realized you might actually want to use an "offset temperature difference", like 7Â°F or something, to keep a constant approach. I'm just note sure how E+ handles having a setpoint that forces approach to be 0Â°F (approach = leaving condenser water temperature - OA Wetbulb temperature)

It'd be nice to have other people chime in as to how they've complied with this in the past.

--
Julien Marrec, EBCP, BPI MFBA
Energy&Sustainability Engineer
T: +33 6 95 14 42 13

LinkedIn (en) : www.linkedin.com/in/julienmarrec
LinkedIn (fr) : www.linkedin.com/in/julienmarrec/fr

2015-11-05 15:05 GMT+01:00 Wenting Ding dingwenting@xxxxxxxxx [EnergyPlus_Support] <EnergyPlus_Support@xxxxxxxxxxxxxxx>:

Â

Julien
Thank you very much. I think I can solve this problem now.
Best regards,
WentingÂ

2015å¹´11æ??5æ?¥æ?¨æ??æ?¥ã??Julien Marrec julien.marrec@xxxxxxxxx [EnergyPlus_Support]<EnergyPlus_Support@xxxxxxxxxxxxxxx>ã??ã??ã?¯æ?¸ã??ã?¾ã??ã??:

Â

Hi,

Unless I'm missing something this isn't complicated. All you need is to put a proper SetpointManager on the Supply Outlet of your ConderserLoop.

I think a SetpointManager:FollowOutdoorAirTemperature does exactly what you need for this Appendix G section:

Design= maximum: 85Â°F / 29.44Â°C
Minimum: 70Â°F / 21.11Â°C

SetpointManager:FollowOutdoorAirTemperature,
Â Â Â MyCondenserControl,Â Â Â Â Â !- Name
Â Â Â Temperature,Â Â Â Â Â Â Â Â Â Â Â Â !- Control Variable
Â Â Â OutdoorAirWetBulb,Â Â Â Â Â Â !- Reference Temperature Type
Â Â Â 0,Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â !- Offset Temperature Difference {deltaC}
Â Â Â 29.44,Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â !- Maximum Setpoint Temperature {C}
Â Â Â 21.11,Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â !- Minimum Setpoint Temperature {C}
Â Â Â Condenser Supply Outlet Node;Â !- Setpoint Node or NodeList Name

Obviously, you'll need to replace "Condenser Supply Outlet Node" with your actual node.

Best,
Julien

--
Julien Marrec, EBCP, BPI MFBA
Energy&Sustainability Engineer
T: +33 6 95 14 42 13

LinkedIn (en) : www.linkedin.com/in/julienmarrec
LinkedIn (fr) : www.linkedin.com/in/julienmarrec/fr

2015-11-05 9:20 GMT+01:00 Jean Marais jeannieboef@xxxxxxxxx [EnergyPlus_Support] <EnergyPlus_Support@xxxxxxxxxxxxxxx>:

Â

This is a bit difficalt to explain quickly.

I recommend the following steps

1) downloading and installing a trail version of designbuilder
2) importing a relevant ASHRAE detailed HVAC system
3) exporting the IDF as a text file
4) comparing the setpoint managers on the different nodes in the idf to the setpoint manager settings on the graphical systems diagram in DesignBuilder.

This will help you understand the connections, settings, etc.

Hope this helps.

On 5 Nov 2015 3:25 am, "dingwenting@xxxxxxxxx [EnergyPlus_Support]" <EnergyPlus_Support@xxxxxxxxxxxxxxx> wrote:

Â

Hi,
Â
Who can tell me how to set the cooling tower temperature as required in ASHRAE Standard 90.1-2007, which need the cooling tower to be contralled to maintain a 70Â°F leaving temperature where weather permits, floating up to leaving water temperature at design conditiongs.
Â
Thank you.
Â
Wenting