Unitary products group FF-07, Руководство по установке

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035-18548-001-B-0203
14 Unitary Products Group
3. Using an inclined manometer, determine the pres-
sure drop across a dry indoor coil. Since moisture
on the coil may vary greatly, measuring the pres-
sure drop across a wet coil under field conditions
would be inaccurate. To assure a dry coil, the heat
pump system should be de-activated while the test
is being run.
4. Knowing the pressure drop across a dry coil, the
actual CFM through a unit can be determined from
the curve in Figure 12.
If the CFM is above or below the specified value, the
supply air motor pulley may have to be re-adjusted.
After one hour of operation, check the belt and pulleys
for tightness and alignment.
After readings have been obtained, remove the tubes
and seal up the drilled holes in the side panel. Dot
plugs (5/16” - P/N 029-13880-000) are available
through normal York parts ordering procedures.
NOTE:
Shut down the heat pump system before tak-
ing any test measurements to assure a dry
indoor coil.
FIGURE 11 - HOLE LOCATIONS FOR PRESSURE
DROP READINGS
5/16"
HOLE
5/16"
HOLE
C
A
EVAPORATOR
COIL
FILTERS
B
D
AIR
IN
Failure to properly adjust the total system CFM
can result in extensive blower damage or sys-
tem damage.
FIGURE 12 - PRESSURE DROP ACROSS A DRY INDOOR COIL VS. SUPPLY AIR CFM
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0.18
2000 2500 3000 3500 4000 4500
CFM
Pressure
Drop
IWG
FF-07