Hello everyone
maybe our first question posted here earlier was not so clear. we just want to know how many critical zones should be put into the spreadsheet with each AHU unit ?? From our understanding , using 62MZ cal spreadsheet and critical zones can be an alternative to calulate the minimum ventilation rate. From 62 MZ cal instructions it provides information on how to define the critical zones in heating or cooling modes. But it does not imply how many critical zones will be enough to put in in each case of AHU calulation ????
for example, one AHU unit serves to total 8 floor plans. For each floor plan there will be critical zones. So should we sum up critical zones from each floor plan and put into the 62MZ cal ? Or should we just use one floor plan as representative one and only count in critical zones from that plan and put into the 62 MZ cal spreadsheet????
we ask these questions here since we tested the 62MZ cal spreadsheet and it felts a bit tricky with inputs for system and inputs for potentially critical zones in the spreadsheet. Even someone suggested here earlier that the input for system can be overriden. Still we want to be sure that we are on the right track.
we really appreciate any advice and hints from anyone who had experience with use of this spreadsheet to earn this credit?
Christopher Schaffner
CEO & FounderThe Green Engineer
LEEDuser Expert
963 thumbs up
November 26, 2012 - 9:07 am
By definition, each air handling system has one critical zone. You should document enough zones to show that you have correctly selected the critical zone.
Sofia Otterheim
November 26, 2012 - 11:26 am
Thank you for your response regarding the critical zones.
However, we have now found an earlier discussion/answer below from Samantha Harrell from the 26th of March 2012.
In our project, our building is supplied with 100% outdoor air. Is it correct that we can not use calculations with critical zones according to 62MZ? Instead, we must use the VRP Compliance Calculator?
If we shall use the VRP Compliance Calculator, must all occupiable areas be included for these calculations (and not only the critical zones). Is this correct?
Christopher Schaffner
CEO & FounderThe Green Engineer
LEEDuser Expert
963 thumbs up
November 26, 2012 - 12:03 pm
Yes. The concept of "critical zones" does not apply to a 100% OA system. Provide the calculation for all the spaces.