Treatment For Long Stoppage Of The Absorption Chiller; Chemical Treatment; Flow Speed In Tubes - York YHAU-CW Manual

FORM 155.31-ICOM2.EN.UL
ISSUE DATE: 12/21/2018
TREATMENT FOR LONG STOPPAGE OF THE
ABSORPTION CHILLER
If the absorption chiller is stopped for 15 days or lon-
ger, bacteria in the water or in the tubes may grow.
The bacteria can corrode the tubes. When stopping the
chiller for more than 15 days, drain the water from the
absorber, condenser, evaporator, and high temperature
generator (steam drain line) through the drain valve at
the bottom of the waterbox.

CHEMICAL TREATMENT

Corrosion inhibitors are attracted chemically to corrod-
ed metal surfaces. Or, they form inert protective com-
pounds over the metal surfaces. For effective use of the
corrosion inhibitors, be sure to choose the correct type
and concentration. Water quality, temperature, flow
speed, metals used, existence of crevices and deposits
and type of water system are also part of the equation.
For more information about corrosion preventive mea-
sures, consult a water treatment company.
JOHNSON CONTROLS

FLOW SPEED IN TUBES

Since the water flow speed in the tubes is closely re-
lated to any existing corrosion, do not increase the wa-
ter supply rate more than recommended. If the flow
speed reaches 11.6 to 13.3 feet per second, the tubes
may erode. When changing the flow rate, contact your
local Johnson Controls Service Center.
If the water supply rate is adjusted at the inlet side of
the heat exchanger (evaporator, condenser, and absorb-
er), the eddy current at the inlet may corrode the tube.
Be sure to control the flow rate on the outlet side.
The eddy current caused by foreign matter in the heat
exchanger is also a factor in corrosion. Be sure to in-
stall a strainer on the inlet side of the heat exchanger
and clean the strainer monthly.
SECTION 7 – MAINTENANCE
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