Water Treatment; Pipework Arrangement; Figure 6 - Two Pass Water Pressure Drop, Si Units; Figure 7 - Pipework Arrangement - York YVAA Installation, Operation & Maintenance Instructions Manual

FORM 201.28-NM1.1
ISSUE DATE: 1/31/2018

FIGURE 6 - TWO PASS WATER PRESSURE DROP, SI UNITS

WATER TREATMENT

The unit performance provided in the Design Guide
is based on a fouling factor of 0.018m2/hr °C/kW
(0.0001 ft2hr°F/Btu). Dirt, scale, grease and certain
types of water treatment will adversely affect the heat
exchanger surfaces and therefore the 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). Johnson Controls recom-
mends that a water treatment specialist should be con-
sulted to determine whether the proposed water com-
position will adversely affect the evaporator materials
of carbon steel and copper. The pH value of the water
flowing through the evaporator must be kept in a range
between 7 and 8.5.
JOHNSON CONTROLS
140
120
100
Evaporator A
80
60
40
20
0
0 20
Water Flow Rate (l/s)
Evaporator C
Evaporator B
Evaporator E
40 60 80

PIPEWORK ARRANGEMENT

The following is a suggested piping arrangement for
single unit installations.
-Isolating Valve - Normally Open
-Isolating Valve - Normally Closed
-Flow Regulating Valve
-Flow Measurement Device
-Strainer
-Pressure Tapping
-Flow Switch
-Flanged Connection
-Pipework

FIGURE 7 - PIPEWORK ARRANGEMENT

SECTION 4 - INSTALLATION
100
LD15147
LD15151
4
41