Based on the July 2010 addendum, MERV 13 Filters are only based on Outdoor air stream. PTAC could not be used with this credit before as MERV 13 needed to be installed on return air (unless getting really fancy custom PTACs).
We are using PTACs and are wondering if MERV 13 filters would be needed on those equipments as we are filing as a natural ventilated building.
Yet, there is an outdoor air damper on the PTAC but it is NOT mechanically operated.
Thanks for your help,
Susan Walter
HDRLEEDuser Expert
1296 thumbs up
July 11, 2011 - 4:51 pm
Okay, I'll give you my thoughts to stimulate comments. Since PTACs are self contained HVAC units, how is the building naturally ventillated in your opinion? The spirit of the credit is to keep contaminants out of the interior environment. How are you doing this with the PTAC? How is this done on naturally ventillated buildings? If it were my project, I would likely consider the PTACs as HVAC equipment and look for a filter on the outdoor air. But I am not a mechanical engineer and do not know the finer points on this issue. However, if you can address how the spirit of the credit is maintained with your solution, then you can likely make a good case to the reviewers.
Erika Duran
Sustainability ConsultantDagher Engineering
72 thumbs up
July 11, 2011 - 5:29 pm
(PTACs used not to be eligible for this credit, as MERV 13 were required on return air stream which was impossible considering the unit.)
Now, concerning filters required on outside air stream:
The PTAC (Packaged Terminal Air Conditioner) is conditioning the air but is not bringing outside air in the dwelling unit. Thus it is not bringing any contaminants to the environment. That's why we call out those spaces "naturally ventilated".
However, we were concerned that the manually operated damper located on the PTAC could be an issue, but it should be considered as a trickle vent more than anything else and in this case we are meeting the credit requirements.
Katherine Ann Resurreccion
Arcadis Philippines, Inc.159 thumbs up
August 3, 2011 - 11:03 pm
Hi Amanda,
Have you already applied for your design review? I have a very similar issue regarding this credit and would want to know more about the review you got from GBCI. I hope you could share if ever. Thanks
Nelina Loiselle
Above Green239 thumbs up
September 17, 2011 - 1:24 pm
Please let me know too, would be very helpful information!!
Nelina Loiselle
Above Green239 thumbs up
June 3, 2013 - 3:37 pm
Any updates on this? Has anyone gotten this credit with PTACs?