McQuay seasoncon ALP-067A, Установка и техническое обслуживание

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Flow Switch for Chilled Water Applications
A WATER FLOW SWITCH MUST BE MOUNTED in either the entering or leav-
ing water line to insure that there will be adequate water flow and
cooling load to the evaporator before the unit can start.
This will
safeguard against slugging the compressors on start up.
It also
serves to shut down the unit in the event that water flow is inter-
rupted to guard against evaporator freeze up.
A flow switch is available from McQuay under ordering number 860-
It is a "paddle"
size from 1" to 6" nominal.
type switch and adaptable to any pipe
Certain minimum flow rates are required
to close the switch and are listed in Table 11. Installation should
be as shown in Figure 13.
TABLE 11 FIGURE 13
FLOW SWITCH MINIMUM FLOW RATES
NOMINAL MINIMUM REQUIRED
PIPE SIZE FLOW TO ACTIVATE
(INCHES) SWITCH (GPM)
1 6.00
1 9.80
1 12.70
2 18.80
2 24.30
3 30.00
4 39.70
5 58.70
6 79,20
FLOW DIRECTION
MARKED ON SWITCH
1.00 NPT FLOW SWITCH
CONNECTION
AFTER BEFORE SWITCH
Electrical connections in the unit control center should be made at
terminals 11 and 12. The normally open contacts of the flow switch
should be wired between these two terminals. There is also a set of
normally closed contacts on the switch that could be used for an in-
dicator light or an alarm to indicate when a "no flow" condition
exists.
Evaporator Fan Interlock for Air Handler Coil Installations
It is important to interlock the air handler evaporator fan with the
condensing unit control center to insure that there will be a cooling
load on the evaporator before the unit can start, to prevent com-
pressor slugging. A pair of terminals for each refrigerant circuit
is available in the unit control center for this purpose.
These
terminal numbers are shown in Figure 12.
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