York Sun Select YV28 - Supply Air Drive Adjustment

Table 66: Dry coil and filter pressure drop
Nominal CFM Dry coil and Filter pressure drop (IWG)
27.5t to 30t 35t 40t 50t
1000 0.02 0.02 0.02 0.02
2000 0.04 0.04 0.03 0.04
3000 0.06 0.07 0.05 0.07
4000 0.08 0.10 0.08 0.10
5000 0.10 0.13 0.10 0.13
6000 0.13 0.16 0.13 0.17
7000 0.15 0.20 0.17 0.21
8000 0.18 0.24 0.20 0.25
9000 0.22 0.29 0.24 0.30
10000 0.25 0.34 0.28 0.35
11000 0.28 0.39 0.32 0.40
12000 0.32 0.44 0.36 0.46
13000 0.36 0.50 0.41 0.52
14000 0.40 0.56 0.46 0.58
15000 0.44 0.62 0.52 0.65
16000 0.49 0.69 0.57 0.73
17000 0.53 0.76 0.63 0.80
18000 0.58 0.84 0.69 0.88
19000 0.63 0.91 0.76 0.96
20000 0.68 0.99 0.82 1.05
Supply air drive adjustment
The RPM of the supply air blower depends on the
required CFM, the unit accessories or options, and
the static resistances of both the supply and the
return air duct systems. With this information, the
RPM for the supply air blower and the motor pulley
adjustment (turns open) can be determined from
the blower performance data tables.
CAUTION
You must adjust the belt drive blower systems to
the specific static and CFM requirements for the
application. The belt drive blowers are not set at
the factory for any specific static or CFM. You must
adjust the blower speed and belt tension.Verify proper
sheave alignment. Tighten the blower pulley and
motor sheave set screws after these adjustments. Re-
check the set screws after 10 to 12 hours of run time.
See the blower motor and drive data table.
Note the following:
• The supply air CFM must be within the
limitations shown in the blower performance
tables.
• You can adjust pulleys in half turn increments.
• Adjust the belt tension.
• Tighten the blower pulley and motor sheave
set screws after any adjustments. Re-check
the set screws after 10 to 12 hours run time.
Table 67: Additional static resistance
Model CFM Cooling only Economizer
6000 0.15 0.09
7000 0.19 0.12
8000 0.23 0.15
9000 0.28 0.19
10000 0.33 0.23
11000 0.39 0.28
12000 0.45 0.33
13000 0.52 0.38
14000 0.59 0.44
15000 0.67 0.50
YV28
YV30
YV35
16000 0.75 0.57
10000 0.33 0.08
11000 0.39 0.10
12000 0.44 0.11
13000 0.50 0.13
14000 0.57 0.15
15000 0.63 0.17
16000 0.70 0.20
17000 0.78 0.22
18000 0.86 0.25
19000 0.94 0.27
YV40
YV50
20000 1.02 0.30
Note:
• For cooling only models, add the
cooling only value to the available static
resistance in the respective blower
performance tables.
• For models with electric heat, add the
electric heat value for your heater size
to the available static resistance in the
respective blower performance tables.
• If the unit contains a reheat coil or
economizer, deduct the corresponding
value from the available external static
pressure shown in the respective blower
performance tables.
• The pressure drop through the
economizer is greater for 100% outdoor
air than for 100% return air. If the
resistance of the return air duct is less
than 0.25 IWG, the unit delivers less CFM
during full economizer operation.
Installation Manual: YORK
®
Sun
™
Select YV28 to YV50
83
Johnson Controls Ducted Systems