Water/Glycol Cooled Unit Piping - Data Aire DAPA-2.5 Installation, Operation & Maintenance Manual

Device is designed to reclose automatically at a predetermined pressure, but reliability of the device to
reseal tightly and to operate at the designed pressure cannot be guaranteed after discharging. Be safe
and replace the device after such an occurrence.

Water/Glycol Cooled Unit Piping

Water/Glycol-cooled units are factory charged and tested. Field supplied and field installed piping is
required from the unit to building water or tower water sources or the fluid cooler (i.e., dry cooler) and
pump package. Pipe size will depend on length of run and the maximum water flow required.
The required field installed fluid cooler pipe sizes may or may not be the same as the connection sizes
on the fluid cooler (Refer to the Fluid Cooler Operation, Installation and Maintenance manual for
connection sizing). This will depend on the length of pipe and the calculated pressure drop of peripheral
components.
Shutoff valves (field provided) should be installed within a few feet of the inlet and outlet connections
of the evaporator to allow the unit to be isolated for service. Drain/fill valves (field provided) should be
located at the lowest point on the connected piping.
Water/glycol cooled units are shipped with plate/fin heat exchangers as standard equipment. A strainer
(Data Aire provided) is shipped loose and is to be field installed in the supply line with shutoff valves
(field provided) before and after the strainer. The strainers and water/glycol piping must be cleaned on
a periodic basis. If the unit is shipped with optional shell and tube condensers, strainers are not required
and not shipped with the unit.
All water pipes have a cap installed on the end of the pipe prior to shipment from the factory for pressure
testing the system. to be removed before installing the piping to the units. Use a tube cutter for smaller
pipes and a reciprocating saw with a metal cutting blade for larger pipe sizes or if there is a clearance
problem. All connections need to be cleaned before connections are brazed together.
The water/glycol system may include a centrifugal pump (or pumps, for redundancy) available from
Data Aire as an option, along with field provided union(s), shutoff valves, check valve(s) and a flow
switch (Data Aire option). Pumps must be primed before operating per the pump manufacturer's
guidelines.
NOTICE: Receivers are often installed on condensers and condensing units.
The receiver includes a safety pressure device to protect the receiver, but the
receiver also includes service valves which, if closed, will isolate this pressure
safety device and only protect the receiver. If these valves are closed, the rest
of the piping system would not be protected from unintended refrigerant
pressure increases. Again, the installing contractor must review the piping
system and guard against trapping the refrigerant by installing field supplied
pressure safety devices.
NOTICE: One of the most common problems in a water/glycol system is the
presence of air in the condenser water loop. Air vents must be installed in
various locations the piping system to purge the air.
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