York STYLE A YCWS, Руководство пользователя

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12 YORK INTERNATIONAL
GUIDE TO SELECTION
Complete water chilling capacity ratings for YORK YCWS
chillers are shown on the following pages to cover the
majority of job requirements. For any application be-
yond the scope of this Engineering Guide, consult your
nearest YORK Office.
SELECTION RULES
1. RATINGS - YCWS 200, 230 380, 460 & 575-3-60 rat-
ing are certified in accordance with ARI standard 550/
590, at the ARI standard condition. Rating not at stan-
dard ARI conditions are rated in accordance with ARI
rating procedures. These ratings may be interpolated
but should not be extrapolated.
2. COOLING WATER QUANTITY - Ratings are based
on 10ºF chilled water range. Use the chilled water
correction factors (below) for other ranges except as
limited by water pressure drop, minimum or maximum
water flows for the cooler.
3. CONDENSER WATER QUANTITY – Rating are ap-
plicable from 2 to 4 gpm/ton as limited by water pres-
sure drop or minimum or maximum water flows for
the condenser. Using the tabulated MBH, the Cond.
GPM is calculated as follows:
Cond. GPM =
MBH x 2
Cond. Water Range (ºF)
4. FOULING FACTORS – Rating are based on 0.0001
evaporator and 0.00025 condenser fouling factor. For
other fouling factors, consult the table below or con-
tact your YORK representative.
EVAP FOULING FACTORS
0.0001 x 0.00025
6 0.9692 1.0015 0.9972 1.0001
8 0.9849 1.0008 0.9980 1.0001
10 1.0000 1.0000 0.9982 1.0001
12 1.0133 0.9993 0.9978 1.0001
14 1.0248 0.9986 0.9979 1.0001
Note: Temperature split factors @ 44ºF Leaving Chilled Liquid Temp
(LCLT)
Selection Data
COND FOULING FACTORS
0.00025 x 0.0005
8 0.9998 1.0004 0.9957 1.0072
10 1.0000 1.0000 0.9959 1.0068
12 1.0001 0.9998 0.9961 1.0065
14 1.0001 0.9998 0.9965 1.0060
Note: Temperature split factors @ 95ºF Leaving Condenser Water
Temp (LCWT).
METHOD OF SELECTION
If the duty requires a 10ºF range on both the cooler and
condenser, see “Ratings”. For water ranges other than
10ºF, use the following procedure.
1. Determine capacity required from the following for-
mula
GPM x Chilled Water Range (ºF)
Capacity (tons) =
24
2. After applying any fouling factor corrections, the ac-
tual condenser heat rejection may be determined as
follows:
Heat Rejection (Btuh) = (Tons x 12,000) + (kW x 3415)
Heat Rejection (Btuh)
Heat Rejection (MBH) =
1000
= (Tons x 12) = (kW x 3.415)
3. Determine condensing water requirements for water
cooled models as follows:
Heat Rejection (MBH) x 1000
Condenser Tons =
15,000
Condenser Tons x 30
Cond. Water GPM =
Condenser Water Range (ºF)
Or combine the two formulas:
MBH x 2
Cond. Water GPM =
Condenser Water Range (ºF)
Temp
Split
Tons
Compr
kW
Tons
Compr
kW
Temp
Split
Tons
Compr
kW
Tons
Compr
kW