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FORM 150.68-ICOM1
ISSUE DATE: 10/15/2020
CHILLED LIQUID SYSTEM
Pressure Tapping
Air vent
Flow Switch
Isolating Valve – Normally Open
Isolating Valve – Normally Closed
Flow Regulating Valve
Strainer
CONNECTION TYPES AND SIZES
Standard pipework connections are of the Victaulic
groove type.
For connection sizes relevant to individual models refer
to the physical data tables in this manual.
WATER TREATMENT
The unit performance given in the Design Guide is
based on a fouling factor of 0.0001 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 pressure drop, reducing the
flow rate and causing potential damage.
Aerated, brackish or salt water is not recommended for
use in the water systems. JCI recommends that a water
treatment specialist be consulted to determine whether
the proposed water composition will not affect the heat
exchanger materials of carbon steel and copper. The pH
value of the water flowing through the unit must be kept
between 7 and 8.5.
22
WATER QUALITY REQUIREMENTS
The water used in the unit liquid system must meet the
requirements detailed in the table below:
Allowable
Item
Unit
Value
pH (25°C)
pH
7.0 to 8.5
SO
ppm
2-
4
HCO
/SO
ppm
_3
_4
CI
ppm
-
PO
ppm
3-
4
NH
ppm
3
Free CI
ppm
Fe
ppm
3+
Mn
ppm
<0.05
2+
CO
ppm
2
H
S
ppm
2
Temp
°C
O content
ppm
Hardness
dH
4.8 to 8.5
Water quality should be inspected before
unit installation and regularly during unit
operation. The water quality must meet the
limits above. If parameters are not within
limits, the heat exchanger may leak or have
problems within scale formation. These
problems may result in the unit not operating
normally, excessive heat exchanger
pressure drops and reduced nominal
capacities.
REFRIGERANT RELIEF VALVE PIPING
The heat exchanger is protected against internal
refrigerant overpressure by refrigerant relief valves. A
pressure relief valve is mounted on each of the main
refrigerant lines connecting the heat exchanger to the
compressors.
For indoor installations, pressure relief valves should
be piped to the exterior of the building.
The size of any pipework attached to a relief valve must
be of sufficient diameter so as not to cause resistance
to the operation of the valve. For critical or complex
installations refer to EN13136.
The internal diameter depends on the length of
pipe required and must be in accordance with local
regulations.
If relief pipework is common to more than one valve its
cross sectional area must be at least the total required
by each valve. Valve types should not be mixed on a
common pipe. Precautions should be taken to ensure
that the exit of relief valves/vent pipe remain clear of
obstructions at all times.
Potential Problem
Corrosion
Fouling
▄
▄
<100
▄
>1.0
▄
<50
▄
<2.0
▄
<0.5
▄
<0.5
▄
<0.5
▄
▄
<10
▄
<50
▄
▄
<65
▄
<0.1
▄
JOHNSON CONTROLS
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