Systems Solution Consultant, LLC
July 23, 2013
Mr. Mike Blanek
Ref: O R Humidity Control
We received the memo from the mechanical contractor regarding the recent work they performed on O R Unit to
achieve the humidity level in space. We also received an email from Mr. Eric Brouillard, stating that the space is
still not achieving the humidity level as required. Assuming the O R Unit is now being retrofitted with
dehumidification control, we can make an educated guess of two potential reason for not achieving the desired
humidity level and they are as follows:
The capacity of the unit is not adequate to remove all the moisture that needs to be removed
The O R Area being open to the recovery area, the unit that is serving the recovery also require to
have dehumidification control.
Pursuant to our review of our construction document, that includes original design document, permit drawings as
well as revised drawings based on contractors suggested changes and their marked up drawings, we would like
to make the following comments based on design criteria per contract drawing:
The total cooling load to achieve the humidity level per Michigan Health Care Facilities Design
Standard is approximately 448 MBH (37 % Latent Load). The final equipment schedule shows the
load required. The unit should be equipped with dehumidification control with hot gas bypass for
The unit that serves adjacent recovery area is also required to have the dehumidification and hot gas
bypass for reheat.
If the installed units meets the above requirement we believe the space will comply with the requirement of
Michigan Health Care Facilities Design Standard
Please see attached, the following
Schedule sheet per Permit Drawings dated 3-30 2012
Schedule sheet per Bulletin 4 (dated 9-28-12) reflecting changes made per contractor’s mark-up
Michigan Health Care Facilities Design Standard for Humidity and temperature requirement.
Shop drawing comments for RTU and Control system.
Thank you
Diptarka Gangulee, PE
Systems solution
1001 Woodward
Detroit 48226
Ph/Fax (313)221 9933
Ph/Fax (734)213 3387
1001 Woodward Ave. Suite #920, Detroit, MI 48226
2900 S. State St., Suite @1, Ann Arbor, MI 48104