A.H.U / Fan Room (p1 of 2) (approx. sizing using rules of thumb)

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Adela Matthews
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1 A.H.U / Fan Room (p1 of 2) M1 STEP 1 Determine air flow req'd for each space, for total size of fan unit(s) in tons. Equation: Area (program) / (sf/ton) = tons req'd for space Classroom 8100sf / 350sf/ton = 23.2 tons Classroom 8100sf / 350sf/ton = 23.2 tons Museum Museum Office Office Lobby Lobby (Note: not including Freight for now) This could be adequate for a Lobby that is less than 50% glass Assuming that the Lobby is mostly glass, and exposed on 3 sides, we will DOUBLE the air requirement in the Lobby tons - Methods of approximating / rough-sizing. Final design process much more involved. - What is a "ton" in HVAC. - Where do these numbers come from (sf/ton by use) cfm/person outside air included in numbers. TOTAL Bldg. Cooling Load: 60 TONS Quick check: Overall Area / Tons =? 20,000 / 60 = 333.3

/ for air speed at coil: Calculate: 24,000 cfm / 500 ft/ = 48 sf SIZE OF COIL = Hdim x Wdim of A.H.U. = 48 SF LENGTH OF A.H.U. = ~ 2 x COIL SIZE M2 1 unit: 48 sf = 6.9'.

2 A.H.U / Fan Room (p2 of 2) STEP 2 Size the fan unit by approximating the size of the coil. o A. For 20 T, use 400 cfm/ton (rule of thumb) for air capacity: Calculate: 60 tons x 400 cfm/ton = 24,000 cfm B. Use (rule of thumb) 500 ft./ for air speed at coil: Calculate: 24,000 cfm / 500 ft/ = 48 sf SIZE OF COIL = Hdim x Wdim of A.H.U. = 48 SF LENGTH OF A.H.U. = ~ 2 x COIL SIZE M2 1 unit: 48 sf = 6.9'... use 1 unit with 7' x 7' coil x 14'L 2 units: (2) at 24 sf = 4.9'... use 2 units with 5' x 5' coil ea. x 10'L 3 units: (3) at 16 sf = 4'... use 3 units with 4' x 4' coil ea. x 8'L STEP 3 Size the coil area and initial supply duct: - Delta T for Austin: 75F to 55F - Speed at air coil. - Machine access / maintenance. A. Max. velocity for forced air = 1,000 ft/ From Step 2: 24,000 cfm / 1000 ft/min = 24sf coil area 1 unit option: 24sf = 4.9'... use 5' x 5' duct (big!) 2 unit option: 12sf ea. = 3.46'... use 3.5' x 3.5' duct ea. coil coil width ~ 4' 2 x coil width A.H.U. coil 3 unit option: 8sf ea. = use 3' x 3' duct ea. NOTE: Main Duct dimension can vary up to 2:1 ratio in section. Fan Room - Preliminary Design Plan Size

Boiler / Boiler Room (p1 of 2) M3 Single-unit design: Determine heat req'd for each space, for total heat in btu's.

wide unit: Boiler Pumps Office 1100 25 27,500 Boiler Room - Preliminary Design Plan Size Lobby 2700 35 94,500 TOTAL HEAT: 543,200 BTU divide by

- Units (sizing boiler): 1 mbh = 1000btu - If > 400,00 btu = "boiler" = required 1-hour rated enclosure, and periodic inspections.

3 Boiler / Boiler Room (p1 of 2) M3 Single-unit design: Determine heat req'd for each space, for total heat in btu's. 5 Equation: Area (program) / (btu/sf) = heat req'd for space Classroom Museum 8100sf 8100 x 28 btu/sf 24 = 226,800 btu 194,400 for shallow, wide unit: Boiler Pumps Office ,500 Boiler Room - Preliminary Design Plan Size Lobby ,500 TOTAL HEAT: 543,200 BTU divide by 1,000 = ~ 543 mbh unit needed. - BTU values for spaces by use (typ. range 24-30). - Units (sizing boiler): 1 mbh = 1000btu - If > 400,00 btu = "boiler" = required 1-hour rated enclosure, and periodic inspections. - If < 200,000 btu = "hot water heater"? Example: HydroTherm ID-85A Boiler 500 mbh 1'-6"W 3'-6"L 2'-6"H Lochinvar 750 btu/hr unit: (Revit module for class) 2'-0"W, 2'-4"L, 4'-4"H Boiler for deep unit: Pumps Boiler Room - Preliminary Design Plan Size

1 unit option: 1 at 500 btu, or 2 unit option: 2 at 300 btu ea., or 3 units option: 3 at 165 btu ea.

4 Boiler / Boiler Room (p2 of 2) M4 Multiple-unit design: Total btu reqd. = 543,000 3 units under 199btu has advantages. Lochinvar mfg. 1 unit option: 1 at 500 btu, or 2 unit option: 2 at 300 btu ea., or 3 units option: 3 at 165 btu ea. (199 btu and under = hot water heater status) 2'-0" Clear, typ. 3 water heaters Manuf: Lochinvar 4'-4"H, 2'-4"L, 2'W Water Heater Room - Preliminary Design Plan Size + 2 pumps in adjacent Chiller Room

Chiller / Chiller Room STEP 1 Determine efficiency / life-span of unit: Least efficient 10-12 year life DX system $3200/ton 25 year life air-cooled system $4800/ton Most efficient 35 year life

5 Chiller / Chiller Room STEP 1 Determine efficiency / life-span of unit: Least efficient year life DX system $3200/ton 25 year life air-cooled system $4800/ton Most efficient 35 year life water-cooled system $6800/ton (Source: S.Allen, rules of thumb based on project histories) York chiller, 118 tons M5 Typically, building will have an air-cooled system if below 300 tons. Water is better (more efficient, longer life-span), typical on big commercial systems over 300 tons. PUMPS: Bell & Gosett (2) HW 1'-5"W, 4'-7"L, 1'-9"H Each (2) CW (2) condensor STEP 2 Choose unit. 5'-0" 60 ton req'd, size water unit is 100 ton (oversized, but fine) York manufacturer, 100 ton unit: 138" L (11'-6) 44" W (3'-8) 73" H Plan for Tube replacement Chiller: McQuay Int. 6'-2"W, 11'-8"L, 8'H Chiller - Difference between 3 systems: how they work. Chiller Room Plan - Preliminary Design Size

More clearance for larger units. Cooling Tower Cooling Tower: Morley 12'-10"L, 10'-7"W, 10'-2"H 8'-0" Typ. clearance all around + must be open to sky.

6 Cooling Tower + Enclosure M6 Choose unit based on # tons required. For our project, 60 ton req'd, size unit is 100 ton. This oversized, but fine as most units run best at about 75% capacity). Manuf: Marley, 100 ton unit: 12' L 4' D 10' H Min. clear around cooling tower: 6' for small units. More clearance for larger units. Cooling Tower Cooling Tower: Morley 12'-10"L, 10'-7"W, 10'-2"H 8'-0" Typ. clearance all around + must be open to sky. Cooling Tower Enclosure - Preliminary Design Plan Note: THIS UNIT IS OUTSIDE (ROOF OR GROUND LEVEL) 2 How cooling towers work, types of systems, vibration and weight. Note: Revit files and product pdf:

7 Electrical and Other Service Rooms M7 OUTSIDE DOOR ELECTRICAL TRANSFORMER: 3'W X 3'L X 5'H ELEC. PANELS, SECURITY, TEL, A.V. OUTSIDE DOOR 5'-0" PANELS 1'-0" Main Electrical Room CITY ELECT SERVICE: 12,000 VOLTS STEP DOWN 1ST OUTSIDE, THEN AGAIN INSIDE MAIN ELECT. RM. Water Service + Fire Protection Room Secondary Elec. Room CONC. PAD ELECTRICAL TRANSFORMER: 6'W X 6'L X 6'H 3'x3' PAD (METER) OUSTIDE PAD-MOUNTED ELEC. TRANSFORMER 8'-0" 8'-0" Pump(s) Hydraulic Elev. Machine Room For Hydraulic elevators (70' max lift): Locate machine room near bottom landing. (hydraulic fluid pumps and panels) For Electric elevators: Locate machine room at roof above top of cab. (electric motorized hoist and panels) I.T. Room: Many buildings will have one I.T. Room per floor (8'x10') with it's own DX cooling system (for internet servers).

Andrea Borowski The Pennsylvania State University University Park, PA November 11, 2002 Consultant: Dr. Bahnfleth Technical Assignment M-3

Andrea Borowski The Pennsylvania State University University Park, PA November 11, 2002 Consultant: Dr. Bahnfleth Technical Assignment M-3 Existing System Evaluation Executive Summary The MBNA Career Services Center is a 44,000 square foot, 4-story office type building at Penn State University, University Park Campus. The building is located