[Equest-users] Gas INFRA-RED radiant heater (UNCLASSIFIED)

[Howe, Timothy]

Having heating and cooling has been a requirement of ASHRAE 90.1 staring with Section 11 in 1999(as far back as I can go) and in both Appendix G and Section 11 in subsequent versions.  LEED only comes into play because it requires the following of the Appendix G.

Also note that addendum to 90.1-2007 has revised the requirement of having cooling in a heating only system which will not have cooling installed in the proposed design.  You are then allowed to model heating only in both baseline and proposed of course.

I tend only to use the thermostat method judiciously when there is a heating system only, the fan power is dramatically less than the baseline allowance (unit heaters or radiation only) and will create an unfair advantage for the proposed system.  

Now to have a kW/CFM input for heating and cooling would be great and remove this issue completely.

Tim.

Timothy Howe, MS, LEED® AP BD+C
Mechanical Engineer
Stantec
61 Commercial Street
Rochester NY 14614
Ph:   (585) 413-5347
Fx:    (585) 272-1814
Cell: (585) 330-8681
www.stantec.com

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-----Original Message-----
From: Eurek, John S NWO [mailto:John.S.Eurek at usace.army.mil] 
Sent: Monday, June 11, 2012 1:36 PM
To: Nick Caton; Howe, Timothy; Karen Walkerman; Pasgar, Arash
Subject: RE: [Equest-users] Gas INFRA-RED radiant heater (UNCLASSIFIED)

Classification: UNCLASSIFIED
Caveats: NONE

Here is what I do for cooling.... And it matches the actual design!!!

Many of the large bay areas are cooled by big exhaust fans.  The fans kick on whenever the zone temperature is above 80 degrees.  The fans are sized to keep the zone temperature no more than 10 degrees above the outside temperature.  So if the design temperature was 85 degrees, the zone temperature should never get above 95 degrees.

I design a cooling system that turns on at 95 degrees.

This method captures the exhaust fan energy and it has a cooling system designed.  

I am also fortunate to have Army standards to reference showing that they approve the 95 degrees as an acceptable condition.

If your space has ventilation cooling, this may be a workable method. 

-----Original Message-----
From: equest-users-bounces at lists.onebuilding.org [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Nick Caton
Sent: Monday, June 11, 2012 11:39 AM
To: Howe, Timothy; Karen Walkerman; Pasgar, Arash; equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] Gas INFRA-RED radiant heater

All,

 

To play devil's advocate:  If you feel a LEED reviewer would approve of modeling a cooling system that simply doesn't do anything, what about simply not define a cooling thermostat schedule?  Makes capacity and unmet hours  both non-issues and the thing will never expend energies trying to cool.  As always, baseline thermostat schedules (or lack thereof) should match the proposed.

 

That said, I'm going to stir the pot and say I'm not advocating this approach.  My reading of 90.1, independent of LEED reviewer commentary, is we're supposed to actually heat and cool all conditioned spaces in the proposed design, even if only heating or cooling is provided.  Providing cooling or heating means in the system set up to never cool or heat misses the point*.    I have not tried addressing the issue in that fashion under a LEED review (on the contrary, I cooled the space in a baseline-equivalent fashion).  I can only caution a reviewer may not agree with the less conservative interpretation - if others have experienced otherwise, please share!

 

~Nick

 

*PS:  Honestly I can only speculate, but I think the "point" of this rule is to not permit an 'unfair' advantage for buildings which do not require heating or cooling for a given area, relative to other buildings going through the performance rating method.  If that's truly the goal, I personally think it would be more elegant to simply have the baseline follow the proposed design's conditioning requirements.  As it stands, it sort of "punishes" building owners/designers for saving energy by recognizing designed conditions of comfort can and should vary by space function.

 

 

cid:489575314 at 22072009-0ABB

 

NICK CATON, P.E.

SENIOR ENGINEER

 

Smith & Boucher Engineers

25501 west valley parkway, suite 200

olathe, ks 66061

direct 913.344.0036

fax 913.345.0617

www.smithboucher.com 

 

From: equest-users-bounces at lists.onebuilding.org [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Howe, Timothy
Sent: Friday, June 08, 2012 12:21 PM
To: Karen Walkerman; Pasgar, Arash; equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] Gas INFRA-RED radiant heater

 

That creates unmet load hours.

 

 

Timothy Howe, MS, LEED® AP BD+C
Mechanical Engineer
Stantec

61 Commercial Street
Rochester NY 14614
Ph:   (585) 413-5347
Fx:   (585) 272-1814
Cell: (585) 330-8681

stantec.com <http://www.stantec.com>  

 

The content of this email is the confidential property of Stantec and should not be copied, modified, retransmitted, or used for any purpose except with Stantec's written authorization. If you are not the intended recipient, please delete all copies and notify us immediately.

 

ü Please consider the environment before printing this email. 

From: equest-users-bounces at lists.onebuilding.org [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Karen Walkerman
Sent: Friday, June 08, 2012 1:05 PM
To: Pasgar, Arash; equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] Gas INFRA-RED radiant heater

 

... so set it to 1

On Fri, Jun 8, 2012 at 1:00 PM, Howe, Timothy <Timothy.Howe at stantec.com> wrote:

Karen,

 

Unfortunately that does not work.  Setting the capacity to zero will just make the program autosize it for you. The only way to prevent the cooling from activating is through the thermostat setting.

 

Tim.

 

Timothy Howe, MS, LEED® AP BD+C
Mechanical Engineer
Stantec

61 Commercial Street
Rochester NY 14614
Ph:   (585) 413-5347 <tel:%28585%29%20413-5347> 
Fx:   (585) 272-1814 <tel:%28585%29%20272-1814> 
Cell: (585) 330-8681 <tel:%28585%29%20330-8681> 

stantec.com <http://www.stantec.com>  

 

The content of this email is the confidential property of Stantec and should not be copied, modified, retransmitted, or used for any purpose except with Stantec's written authorization. If you are not the intended recipient, please delete all copies and notify us immediately.

 

ü Please consider the environment before printing this email. 

From: Karen Walkerman [mailto:kwalkerman at gmail.com] 
Sent: Friday, June 08, 2012 12:49 PM
To: Howe, Timothy
Cc: Pasgar, Arash; equest-users at lists.onebuilding.org <mailto:equest-users at lists.onebuilding.org> 
Subject: Re: [Equest-users] Gas INFRA-RED radiant heater

 

"Technically you need to model both heating and cooling in the baseline and proposed"

 

... only for LEED models.

 

You can also model a different HVAC system that includes cooling (and allows for a baseline), and simply set the cooling capacity to 0.

 

--

Karen

 

On Fri, Jun 8, 2012 at 12:39 PM, Howe, Timothy <Timothy.Howe at stantec.com> wrote:

Technically you need to model both heating and cooling in the baseline and proposed

 

 


Classification: UNCLASSIFIED
Caveats: NONE