York EX Series - Precautions for the Use of Water; Chilled;Hot Water Outlet Temperature Controller; Liquid Level Gauges; TABLE 29 - Liquid Level Gauges (Sight Glass)

JOHNSON CONTROLS
78
FORM 155.32-ICOM1.EN.GB
ISSUE DATE: 10/13/2017
SECTION 5 - COMMISSIONING
PRECAUTIONS FOR THE USE OF WATER
Staining and corrosion of the tubes in the evapora-
tor, absorber, and condenser depends on the quality of
the water used as chilled/hot water and cooling water.
Water quality must be checked periodically to pre-
vent problems. If water quality is not controlled and
maintained properly, premature tube failure can result.
Causes of bad quality water include:
• Polluted seawater
• Polluted underground water
• Cooling tower located near a chimney or in dirty
air
Be sure to analyze the chilled/hot water
and the cooling water within one month
after commissioning. See Table 23 on
page 153.
Install strainers of 10 mesh and above to the chilled/hot
water and cooling water inlets.
Shut off valves will be installed at the customer site
in the chilled/hot water, and cooling water inlets and
outlets. Be sure the valves are completely open when
suppling water. If not, the water flow can become tur-
bulent (at the shut off valves) and damage the water
chamber case and tubes. When you need to reduce the
quantity of the chilled/hot water, and cooling water
temporarily, use the valves to make adjustments.
When the flow rate change of the chilled/hot water is
controlled (if the flow rate change function is installed),
the load change speed is limited.
• The load change condition to limit the chilled/hot
water temperature at the outlet is ±0.5°C : 1.5%/
minimum maximum.
• The critical load change condition to prevent an
overcooling trip of the chiller-heater is 5%/mini-
mum maximum.
CHILLED/HOT WATER OUTLET
TEMPERATURE CONTROLLER
The chilled/hot water outlet temperature controller
(23A) is located on the sequencer and controls the
chilled/hot water outlet temperature.
LIQUID LEVEL GAUGES
Liquid level gauges are used to check the conditions of
the chiller-heater components.
TABLE 29 - LIQUID LEVEL GAUGES (SIGHT
GLASS)
LIQUID LEVEL
GAUGE NAME
SYMBOL FUNCTION
Refrigerant overow
monitoring level gauge
G101
Checks refrigerant
overow level
Refrigerant tank level
gauge
G102
Checks lower limit of
refrigerant tank level
Absorber level gauge G103
Checks lower limit of
absorber
HT-GEN level gauge G104
Checks condition
of solution in high-
temperature generator
LT-GEN level gauge G105
Checks condition
of solution in low-
temperature generator