5.8.4 Waterside Economizer Effectiveness and Controls

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What NACM Section(s) are relevant to this issue?

5.8.4 Waterside Economizers

Explanation of issue:

1. The equation for effectiveness is wrong
2. E+ does not appear to have an input for WSE effectiveness. They use the NTU 
method, which requires inputs of UA values. Should we accommodate this, or just 
require effectiveness as an input?
3. Water-side Economizer Maximum Tdb - this is not the best way to control 
economizer.

Proposed resolution:

1. Updating equation
2. Ideally, require effectiveness input. But can E+ transform this to a UA for 
the heat exchanger???
3. Replace this field with temperature difference between chilled water inlet 
and condenser water inlet to HX. (used in E+). 

Please provide any additional information below.

Original issue reported on code.google.com by JohnJArent on 4 Apr 2013 at 8:53

[GoogleCodeExporter]

Made significant changes to this section:

Modified effectiveness equation.

Removed Maximum Tdb control and added WSE Operating Range field for control - 
WSE is enabled whenever the temperature difference exceeds a specified amount

Removed WSE CWS Setpoint building descriptor

Original comment by JohnJArent on 2 May 2013 at 5:29

• Changed state: Resolved

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Original comment by JohnJArent on 7 Feb 2014 at 7:45

• Changed state: DoneVerified