[Equest-users] Caution Message

[Bishop, Bill]

Rakesh,

Your caution message showed output of 1.372, so you would have to increase your OUTPUT-MAX to 1.4 or higher. That might make the caution message go away, but doesn't address the reason that your fan part load is so high. I don't know what it could be.
Note that "caution" and "warning" messages are not as critical as "error" messages. If you post your .inp and .pd2 files, someone may open your model and take a look.

Regards,
Bill

From: Rakesh Desai [mailto:rakeshdesai at ecpl.co.in]
Sent: Wednesday, April 10, 2013 12:12 AM
To: Bishop, Bill; equest-users at lists.onebuilding.org
Subject: RE: [Equest-users] Caution Message

Bill,

I tried to reduce the MAX-FAN_RATIO to 1.0 but the caution message propped up.

As suggested by you, I changed max output ratio to 1.20 in the curve but received the attached message.

What should be next step?

Rakesh

From: Bishop, Bill [mailto:bbishop at pathfinder-ea.com]
Sent: Tuesday, April 09, 2013 7:14 PM
To: rakeshdesai at ecpl.co.in<mailto:rakeshdesai at ecpl.co.in>; equest-users at lists.onebuilding.org<mailto:equest-users at lists.onebuilding.org>
Subject: RE: [Equest-users] Caution Message

Rakesh,

The FC-Fan-w/Dampers curve determines fan power as a function of part load. I'm guessing that the system that you have applied this curve to has a MAX-FAN-RATIO greater than one, which is causing the output of the curve to exceed the OUTPUT-MAX.
The OUTPUT-MAX for the curve is 1.05, as shown on the warning message and in the curve properties dialog box (see below).
The warning message is showing that the fan power is being limited to the maximum allowable by the curve. The flow through the supply fan is exceeding 100% of design value, but the power is not increased accordingly.
You can reduce the MAX-FAN-RATIO to 1.0 assuming the fan is limited in that way. Alternatively, you could increase the curve OUTPUT-MAX, either in the library curve or by creating a new curve as I have shown below. This will extrapolate values of the curve beyond their intended range, so the accuracy of the fan power at greater than design flow may be a little off, but it is certainly better than not making any changes.

Regards,
Bill

[cid:image001.jpg at 01CE35C6.CFA09F10]

[cid:image002.jpg at 01CE35C6.CFA09F10]

William Bishop, PE, BEMP, LEED AP | Pathfinder Engineers & Architects LLP
Senior Energy Engineer

134 South Fitzhugh Street                 Rochester, NY 14608
T: (585) 325-6004 Ext. 114            F: (585) 325-6005
wbishop at pathfinder-ea.com<mailto:wbishop at pathfinder-ea.com>           www.pathfinder-ea.com<http://www.pathfinder-ea.com/>
P   Sustainability - the forest AND the trees. P

From: equest-users-bounces at lists.onebuilding.org<mailto:equest-users-bounces at lists.onebuilding.org> [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Rakesh Desai
Sent: Tuesday, April 09, 2013 8:40 AM
To: equest-users at lists.onebuilding.org<mailto:equest-users at lists.onebuilding.org>
Subject: [Equest-users] Caution Message

Hello,

While running my proposed case, I am getting the attached caution message.

Can anyone help me to understand what it is meant and how to solve the problem?

Thanks.

Rakesh Desai
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20130410/88552109/attachment-0002.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.jpg
Type: image/jpeg
Size: 18192 bytes
Desc: image001.jpg
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20130410/88552109/attachment-0004.jpg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image002.jpg
Type: image/jpeg
Size: 20434 bytes
Desc: image002.jpg
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20130410/88552109/attachment-0005.jpg>