[Equest-users] eQUEST - serious trouble with LEED review

[Brian Fountain]

With respect to your first point, you can have either a single loop 
pump, a chiller pump or both.  (this can be set up in the wizard or 
detailed interface -- obviously you are well into the detailed interface 
on this project.)

For each chiller in eQUEST, one of the tabs is "loop attachments" where 
you can specify a chiller chilled water pump and a chiller condenser 
water pump which will then operate with the chiller.  Once you have 
defined the pumps there, you can delete the main loop pump.

Note that I have found it helpful to save and then reopen and eQUEST 
file once water side changes have been made -- especially when you are 
reconfiguring loops and pumps.  Sometimes saving and reopening clears 
.bdl errors that would otherwise crop up.


With regard to your 2nd query, I have not had time to open your file.  
You can change the loop "sizing option" from secondary (where it adds up 
all connected coil capacities) to primary (where it looks at capacity of 
primary equipment on the loop).  Perhaps this may resolve the issue.  
Apologies if I missed the point on this one.





On 1/24/2011 12:27 PM, Heinrich.ib-bauklima.de wrote:
>
> Hi Everyone,
>
> I got a review comment that got me in big trouble and I can't find the 
> solution yet.
>
> May be there is no solution for this in eQUEST....!
>
> I rate this forum as the very best address for difficulties with 
> eQUEST and LEED EAc1 simulation.
>
> So please give me some guidance and feel free to test the model attached.
>
> Here are the two comments of the reviewer.
>
> /"It appears as if the pumps and circulation loops were not modeled 
> correctly for the Baseline Case. It appears based on the PS-C reports 
> that there is only one primary chilled water pump and one condenser 
> water pump for the Baseline Case. However, ASHRAE 90.1 Section G3.1.11 
> requires that each chiller be modeled with separate condenser water 
> and chilled water pumps interlocked to operate with each associated 
> chiller. Please model two primary chilled water pumps and two primary 
> condenser water pumps in accordance with Section G3.1.11. Also update 
> the chilled water valves to two-way valves so that the secondary 
> chilled water loop operates as a variable flow loop with pumps riding 
> the curve. Provide updated PS-C reports confirming that the changes 
> have been made."/
>
> /"It is unclear why the pump flow for the secondary chilled water loop 
> is so much larger than that of the primary chilled water loop when the 
> temperature differential for both loops is expected to be the same. It 
> also appears based on the outputs in PS-C that the secondary chilled 
> water loop is operated at the same load for every hour that it is on 
> even though it is a variable speed pump. Please update the secondary 
> chilled water loop flow to be consistent with the primary chilled 
> water loop flow, and confirm that the secondary chilled water loop is 
> operating as a variable flow loop."/
>
> I have to say:
>
> I didn't see any equest-model modeled with separate condenser water 
> and chilled water pumps interlocked to operate with each associated 
> chiller.
>
> I manually resized the boilers and chillers with reference to SS-D 
> report, because auto sizing of eQUEST generated capacities that were 
> double the size of SS-D report. Resizing of the volume flow of 
> secondary loop of chillers according to primary loop of chillers 
> generated warning messages but changed nothing.
>
> Heinrich
>
>
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