York YACT038-072, Руководство по установке

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Operating Limits
Operating Limits
Cooling Heating
°F °C °F °C
Air Limits
Minimum Ambient Air 45 7.2 45 7.2
Rated Ambient Air 80 26.7 70 21.1
Max. Ambient Air 100 37.8 85 29.4
Minimum Entering Air 50 10.0 40 4.4
Rated Entering Air db/wb 80.6/66.2 27/19 68 20.0
Maximum Entering Air db/wb 110/83 43/28.3 80 26.7
Water Limits
Minimum Entering Water 30 -1.1 20 -6.7
Normal Entering Water 50-110 10-43.3 30-70 -1.1
Maximum Entering Water
120 48.9 90 32.2
NOTES: Minimum/maximum limits are only for
start-up conditions, and are meant for bringing the
space up to occupancy temperature. Units are not
designed to operate at the minimum/maximum
conditions on a regular basis. The operating limits
are dependant upon three primary factors: 1) water
temperature, 2) return air temperature, and 3)
ambient temperature. When any of the factors are
at the minimum or maximum levels, the other two
factors must be at the normal level for proper and
reliable unit operation.
HE
gpm x 500
Reference Calculations
Heating Calculations: Cooling Calculations:
LWT = EWT +
LAT (DB) = EAT (DB) -
LC = TC - SC
S/T =
HR
gpm x 500
SC
cfm x 1.08
SC
TC
LWT = EWT -
LAT = EAT +
TH = HC + HW
HC
cfm x 1.08
Legend and Notes
Abbreviations and Definitions
cfm = airflow, cubic feet/minute
COP = Coefficient of Performance
= Btu output/Btu input
= [HC/(kw x 3.413)]
EAT = entering air temperature, °F
EER = Energy Efficient Ratio
= Btu output/Watt input
ELT = entering load fluid temperature to heat pump
EST = entering source fluid temperature to heat pump
EWT = entering water temperature (source) to heat pump
FT HD = pressure drop in feet of head
GPM = Gallons per minute
WPD = water pressure drop, psi and feet of water
HC
= air heating capacity, MBtu/h
HE = total heat of extraction, MBtu/h
HR = total heat of rejection, MBtu/h
kW = total power unit input, kilowatts
LAT = leaving air temperature, °F
LC = latent cooling capacity, MBtu/h
LGPM = load flow in gallons per minute
LLT
= leaving load fluid temperature from heat pump
LST = leaving source fluid temperature from heat pump
LWPD = load coax water pressure drop
LWT = leaving water temperature, °F
PSI
= pressure drop in pounds per square inch
S/T = sensible to total cooling ratio
SC = sensible cooling capacity, MBtu/h
SWPD= source coax water pressure drop
TC
= total cooling capacity, MBtu/h
TH = total heating capacity, MBtu/h
WPD = water pressure drop in PSI, feet of water
Notes to Performance Data Tables
The following notes apply to all performance data tables:
• Performance ratings are based on 80°F DB/67°F WB EAT for cooling and 70°F DB EAT for heating.
• Three flow rates are shown for each unit. The lowest flow rate shown is used for geothermal open loop/well water systems
with a minimum of 50°F EWT. The middle flow rate shown is the minimum geothermal closed loop flow rate. The highest
flow rate shown is optimum for geothermal closed loop systems and the suggested flow rate for boiler/tower applications.
• The hot water generator numbers are based on a flow rate of 0.4 gpm/ton of rated capacity with an EWT of 90°F.
• Entering water temperatures below 40°F assumes 15% antifreeze solution.
• For non-standard EAT conditions, apply the appropriate Correction Factor tables.
• Interpolation between EWT, gpm, and cfm data is permissible, extrapolation is not.
• Pumping power is not included in the Performance Data tables nor are calculations for AHRI/ISO 13256-1.
AFFINITY COMBINATION INSTALLATION MANUAL