York DY 036 - Manual (Page 18)

343615-YTG-A-0807
18 Unitary Products Group
1. Deduct these resistance values from the available external static pressure shown in SUPPLY AIR BLOWER PERFORMANCE Tables.
2. Add these resistance values to the available static resistance values on SUPPLY AIR BLOWER PERFORMANCE Tables.
3. The pressure through the economizer is greater for 100% outdoor air than for 100% return air. If the resistance of the return air duct system is less than
0.25 IWG, the unit will deliver less CFM during full economizer operation.
TABLE 21: STATIC RESISTANCES
DESCRIPTION
RESISTANCE, IWG
CFM
1000 1200 1400 1600 1800 2000 2200 2400 2600 2800 3000
ECONOMIZER 1,3 0.07 0.08 0.09 0.11 0.13 0.15 0.17 0.20 0.23 0.26 0.30
ELECTRIC
HEATERS 1
7-15KW 0.04 0.05 0.06 0.07 0.08 0.10 0.12 0.14 0.16 0.19 0.22
20-30KW 0.06 0.07 0.08 0.09 0.11 0.13 0.15 0.17 0.20 0.23 0.26
COOLING ONLY 2 0.08 0.10 0.12 0.14 0.16 0.18 0.20 0.23 0.26 0.29 0.32
TABLE 22: ELECTRIC HEATER CFM LIMITATIONS
UNIT MODEL SIZE
NOMINAL TONS
VOLTAGE
MINIMUM SUPPLY AIR CFM
HEATER SIZE NOMINAL KW
5 7 10 15 20 30
3
208/230-1-60 1100 1100 1200 1200 1300 -
208/230-3-60 1100 1100 1200 1200 1300 -
460-3-60 - 1100 1200 1200 1300 -
575-3-60 - - 1200 1200 1300 -
4
208/230-1-60 1300 1300 1300 1300 1300 -
208/230-3-60 1300 1300 1300 1300 1300 -
460-3-60 - 1300 1300 1300 1300 -
575-3-60 - - 1300 1300 1400 -
5
208/230-1-60 1600 1600 1600 1600 1600 1600
208/230-3-60 1600 1600 1600 1600 1600 1600
460-3-60 1600 1600 1600 1600 1600 1600
575-3-60 - 1600 1600 1600 1600 1800