3.7.3.2 - Fan curves

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What 90.1 PRM Section(s) are relevant to this issue?

Table 39

Explanation of issue:
I think we decided to use the Title 24 default fan curves in the PRM. However, 
I noticed that the default curve for "Fan with VSD and Perfect SP Reset" form 
the Advanced VAV Guidelines. This represents a VAV fan system with no terminal 
units and is not appropriate for a standard reheat VAV system. It is more 
appropriate to use the "Good SP reset" curve from the guidelines. 

Proposed resolution:

Original issue reported on code.google.com by bikerose...@gmail.com on 6 Oct 2014 at 11:37

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I also noticed your curves only go down to 10% power. That means 10% energy use 
when the fan is off. The Taylor curves go down to 0% power. 

Original comment by bikerose...@gmail.com on 6 Oct 2014 at 11:41

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I added an owner and description of this issue for tracking. 

I've added the Good SP Reset curve to our library, and will update the rules to 
use this curve for PVAV and VAV systems.  

The min output definition is not intended to be the power used even when the 
fan is off.  If the fan is scheduled off, it uses 0 power.  The min output 
defines the minimum power used when the fan is scheduled on or cycles on to 
meet a load.

I tend to agree, having a minimum output for the curve is a bit odd; I think 
the min power is better defined by the minimum flow of the system.  The 
minimums were defined in the NACM; if you want a lower minimum power or no 
power minimums for 90.1, just let us know.

Original comment by da...@360-analytics.com on 14 Oct 2014 at 5:08

• Changed title: 3.7.3.2 - Fan curves
• Changed state: New