Using the 62MZ calculator

February 10, 2014

Christina Reeves

Principal Environmental Specialist
Progressive Associates

LEEDuser Basic Member

February 10, 2014

Hello, I have two questions from our ME about using the spreadsheet calculator:
1. Neither of us can get the macros to work on the calculator - to add zones, etc. We both choose 'enable Macros' when opening the file but the buttons still don't work. He is on PC and I'm on a Mac, so platform isn't the issue. Does anyone have tips for this?

2. Is there any guidance out there for how to use the calculator with demand-controlled ventilation?

Thanks much!

Post a reply

Ben Stanley

Senior Sustainability Manager
WSP - Built Ecology

LEEDuser Expert

250 thumbs up

February 10, 2014 - 12:06 pm

Christina,

I've been able to use the macros on PC's but never on a Mac. I'm not sure what the issue might be in this case. What about using the form calculator instead?

For the demand control ventilation, I would still set up the calculations and testing to reflect the scenario where the potentially critical zones are fully occupied and the fans and outside air dampers are set to the lowest point (worst case condition typically in the heating season). Also, if the CO2 sensors are located in the return duct, the review team will likely request justification for how those sensors are accurately accounting for the CO2 in the breathing space of the occupied spaces.

Julia Weatherby

President
Weatherby Design & Co. Engineers

LEEDuser Basic Member

94 thumbs up

February 10, 2014 - 12:19 pm

Christina-

On a PC, sometimes if the security level for macros is set to high or very high then even enabling macros will not allow them all to run. I would think you would get a warning message about that though, so that might not be the problem. Your ME on the PC could try downloading a fresh copy (or a copy from a different source) of the spreadsheet and trying again, making sure the security setting under macros is set to medium. Also try the help troubleshooting menu for macros from within Excel.

As Ben wrote, demand control ventilation does not necessarily come into play for the ventilation rate spreadsheet. You can use the design ventilation values for the spreadsheet, ignoring the demand control ventilation. Then the demand control ventilation is added as part of the control system.