Technical data

4.8 Evaporator and Condenser Water Piping
The evaporator and condenser liquid heads have
nozzles which are grooved, suitable for welding 10.6 bar
DWP flanges or the use of Victaulic couplings. Factory
mounted flanges are optional.
The nozzles and water pass arrangements are
delivered in accordance with the job requirements (see
Product Drawings delivered with the job and Section 9).
Standard units are designed for 10.6 bar DWP on the
water side. If job requirements are for greater than
10.6 bar DWP, check the unit Data Plate before applying
pressure to evaporator or condenser to determine if the
chiller has provisions for the required DWP.
Inlet and outlet connections are identified by labels
placed adjacent to each nozzle.
Foreign objects which could lodge in, or block flow
through the evaporator and condenser tubes must be
kept out of the water circuit. All water piping must be
cleaned or flushed before being connected to the chiller
pumps, or other equipment.
Permanent strainers (supplied by others) are required in
both the evaporator and condenser water circuits to
protect the chiller as well as the pumps, tower spray
nozzles, chilled water coils and controls, etc. The
strainer should be installed in the entering chilled water
line, directly upstream of the chiller.
Water piping circuits should be arranged so that the
pumps discharge through the chiller, and should be
controlled as necessary to maintain essentially constant
chilled and condenser water flows through the unit at all
load conditions.
If pumps discharge through the chiller, the strainer may
be located upstream from pumps to protect both pump
and chiller. (Piping between strainer, pump and chiller
must be very carefully cleaned before start-up.) If pumps
are remotely installed from chiller, strainers should be
located directly upstream of the chiller.
4.9 Water Treatment
The unit performance given in the Design Guide is
based on a fouling factor of 0.044 m² °C/kW (0.00025
ft²hr °F/Btu). Dirt, scale, grease and certain types of
water treatment will adversely affect the heat exchanger
surfaces and therefore unit performance. Foreign matter
in the water system(s) can increase the heat exchanger
pressure drop, reducing the flow rate and causing
potential damage to the heat exchanger tubes.
Aerated, brackish or salt water is not recommended for
use in the water system(s). York recommend that a
water treatment specialist is consulted to determine that
the proposed water composition will not affect the
evaporator materials of carbon steel and copper.The pH
value of the water flowing through the heat exchangers
must be kept between 7 and 8.5.
160.81-ICOM-GB0 (01/02) 4-3
Figure 4.3 Typical Piping Arrangement