Stulz CeilAiR Series, Инструкция по установке, эксплуатации и обслуживанию

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(Mar, 2012)
CeilAiR OHS Series Installation, Operation & Maintenance Manual
Air Technology Systems, Inc.
3. Remove the blower belt(s).
4. Loosen the set screw in the side of the sheave
with an Allen wrench.
5. Remove the sheave key.
6. Adjust the blower speed by closing the sheave
one half turn to increase speed or opening the
sheave one half turn to decrease speed.
7. Replace the sheave key and tighten set screw.
8. Proper belt tension is achieved when the belt
has a defl ection of ¾ inch per foot of span
between the blower and motor pulleys, with a
fi rm pressure placed on the side of the blower
belt. Adjust the blower belt tension by raising (to
tighten) or lowering (to loosen) the nuts on the
adjustment rods of the motor base.
CAUTION
If the belt tension is too tight, it will cause pre-
mature blower and/or motor bearing failure. If
the belt is too loose, the belt will slip and cause
belt squeals and eventual belt failure.
9. Restore power to system.
10. Check the current draw on the blower motor to
make sure it does not exceed the nameplate
rating of the motor.
11. If current draw exceeds nameplate rating of
motor repeat steps 1 through 9 to decrease
blower speed. If the motor pulls too much
current, slow the blower down by opening the
adjustable sheave one half turn at a time until the
motor current is at or below the nameplate FLA.
12. Check the motor overload on the blower starter
to confi rm its setting is correct for the FLA of the
motor.
2.9.5.2 EC Blower(s)
The speed of the EC Blowers is controlled via a
0 to 10 VDC signal from the system controller.
The controller is set by the factory and should not
require adjustment. If it is determined that the air
fl ow needs adjustment, this may be done using the
controller’s programming menu selections. Refer to
the operator’s manual provided under separate cover
for the system controller. It is recommended that
SATS Product Support be contacted before making
adjustments to the controller.
2.9.6 Thermal Expansion Valve
All CeilAiR units utilizing thermal expansion valves
(TEV) control the fl ow of refrigerant entering the
evaporator to maintain a constant superheat of the
refrigerant vapor at the outlet of the evaporator.
Superheat is the difference between the refrigerant
vapor temperature and its saturation temperature
at that pressure. By controlling superheat, the TEV
keeps nearly the entire evaporator surface active
while not permitting liquid refrigerant to return to the
compressor. The standard super-heat is factory set at
12-15°F and should not need adjustment.
2.9.7 Hot Gas Reheat (Optional)
The hot gas reheat option incorporates a hot gas
reheat solenoid valve and a hot gas reheat coil.
Under normal operation when no reheat is required,
the hot gas reheat valve is de-energized and hot
gas fl ows directly from the compressor discharge
to the condenser. When there is a call for reheat,
the controller energizes the hot gas reheat solenoid
valve. The hot gas reheat solenoid valve diverts hot
gas to the reheat coil, mounted directly downstream
of the evaporator coil, before it travels to the
condenser. No adjustment to the valve is necessary.
2.9.8 Hot Gas Bypass (Optional)
The two most common systems provided by SATS
for hot gas bypass are snap acting and full fl oating
described as follows.
2-24
Figure 13- Belt Drive Blower