The document analyzes the best HVAC system for a retail store called Discount Dan's located in Biloxi, Mississippi. It recommends a heat pump, split duct, single zone, constant volume system because it has low initial and operating costs, requires minimal maintenance, and would not cause the store to close if one component failed. The system was chosen because heat pumps are efficient, do not require gas lines, and could provide both heating and cooling for the store given its mild climate. Three COP 3 heat pump units with air handlers would meet the heating and cooling needs of the 15,000 square foot store.

1. Nate Lee W 846188
Dr. Mohd Shiratuddin
AEC 315: Mechanical Systems
September 17, 2012
Case Study: Building
For Discount Dan’s, using a heat pump, split duct, single zone, constant volume system
will work best. There are many ways to design HVAC systems yet the certain criteria set by the
building owner suggest an inexpensive yet high quality system for customer satisfaction and
enjoyment. Situated at the mouth of the Gulf of Mexico, Discount Dan’s is a national retail
located in Biloxi, Ms. This particular store faces south and has a flat light colored roof. Most
stores are standard 30’ by 50’ with 15’ walls. The interior of the stores are not partitioned off
therefore, it is one large interior room. The outside “skin” of the building is made of corrugated
steel and fiberglass. The requirements of this project are as follows. The initial cost must be low.
The operating cost should be efficient. There should be minimal equipment maintenance.
HVAC failure should not close the store.
Low initial cost and operating cost are anticipated. Minimal equipment maintenance is
desired and equipment failure of one part of the unit should not close the store. Because of these
criteria for the HVAC system, a heat pump system will be used. No gas lines are needed and this
will save on installation. Heat pumps can be a higher system for the initial installation but heat
pumps systems use resources that are already available. Another upside to heat pumps are latent
and radiant heat from the environment can be used which will also save money. Because this
particular Discount Dan’s location enjoys mild winters, the unit will fare well.

2. Heat pumps can also cool during the summer months which mean there is no reason to
buy extra machinery for cooling purposes. Three COP 3 units with air handlers will be efficient
enough to heat and cool the building with no problem. These units will be able to take up slack
if one of the units were go out. A split system with air handlers will be used to push the air
through the ducts. The ducts will run a single zone with constant volume air. The ducts, being
inside the conditioned area will aid in efficiency. Exhaust fans and floor vents with vats will be
utilized seasonally to increase efficiency.
Heat pumps were chosen because they have dual functions, also no gas line need be
installed. It is of good concern also that the noise of the unit may irritate customers, so the unit
will be installed on the roof. The air will be at a constant volume of air, because it’s less
expensive and also the entire building will be either heated or cooled. As for the ascetics, the
duct work will be woven into the rafters and painted the same color as the ceiling, to blend in.
As far as maintenance, it should be low, however attached are three businesses that contract parts
and labor for the life of the machine.
The best option is a heat pump, split duct, single zone, and constant volume system. No
gas line needs to be installed and the split duct system is more efficient. The room is open space
that does not need dual functioning units, both heating and cooling at the same time. Because
this unit works hardest during summer, it is imperative that the system is of quality and efficient.
The building space is 15,000 square feet. The “U” of the building is .25. The max temperature
difference in the winter should be around 57 degrees, taking into account 20 degree F outside
and 77 degree F inside. With this calculation, the total BTUH’s lost amount to 21,375 BTUH.
Three COP 3 heat pump systems would be 30,600 BTUH. This system should work equally well
in the summer. Customer complacency is important because if they are uncomfortable while

3. shopping, profits could drop. There are many ways to design a HVAC system. Although there
are many ways, the heat pump system, with single zone ducts fit the building owner criteria best.