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<p class=MsoNormal>My question regards Section 6.5.3.2.1 Part-Load Fan Power
Limitation from ASHRAE Standard 90.1-2004, which states:<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"TT118Co00","sans-serif"'>6.5.3.2.1 </span><b><span
style='font-size:10.0pt;font-family:"Times New Roman","serif"'>Part-Load Fan
Power Limitation. </span></b><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'>Individual<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Times New Roman","serif"'>VAV fans with motors 15 hp and larger
shall meet one of<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Times New Roman","serif"'>the following:<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Times New Roman","serif"'>(a) The fan shall be driven by a
mechanical or electrical variable-<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Times New Roman","serif"'>speed drive.<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Times New Roman","serif"'>(b) The fan shall be a vane-axial fan
with variable-pitch<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Times New Roman","serif"'>blades.<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Times New Roman","serif"'>(c) The fan shall have other controls
and devices that will<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Times New Roman","serif"'>result in fan motor demand of no more
than 30% of<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Times New Roman","serif"'>design wattage at 50% of design air
volume when static<o:p></o:p></span></p>
<p class=MsoNormal style='text-autospace:none'><span style='font-size:10.0pt;
font-family:"Times New Roman","serif"'>pressure setpoint equals one-third of
the total design static<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:"Times New Roman","serif"'>pressure,
based on <i>manufacturer’s </i>certified fan data.</span><o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I have a project that is using Fanwall technology in the air
handlers that serve the VAV system. The air handler has 3 rows of 8 fans
each of them only 7.5 hp each (at total of 24 – 7.5 hp fans for a total
of 180 hp). When the Standard here says “Individual VAV fans…”
is it saying that for this type of air handler where no individual fan exceeds
15 hp that part-load control is not required? Certainly, if this is true,
using this technology would be great for demonstrating energy points (aka
LEED), but I’m having a hard time justifying this in my mind.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Does anyone know if this Section applies to “fanwall”
technology or if it is simply intended to make distinction between supply,
return, relief, and exhaust fans?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thanks,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='font-size:14.0pt;font-family:Cheltenham;
color:#A0002F'> </span><span style='font-size:18.0pt;font-family:Cheltenham;
color:#A0002F'>Dan Russell, EIT <o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:Cheltenham;
color:#A0002F'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.0pt;font-family:Cheltenham;
color:#A0002F'><img width=200 height=174 id="Picture_x0020_1"
src="cid:image001.jpg@01C90759.97D17460"
alt="cid:image001.jpg@01C840A4.E711B250"></span><o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
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