SECTION 7 – MAINTENANCE
FORM 155.32-ICOM2.EN.UL
ISSUE DATE:1/10/2018
152
JOHNSON CONTROLS
Table 42 -
Wet Storage Method
Table 43 -
Dry Storage Method
PART
STORAGE METHOD
NOTES
Storage Period;
less than 2
months
Chilled/hot water
line
Filled with water
1. The manual valve on the purge piping should be fully closed. See
2. If the storage period exceeds 2 months, algae and bacteria may propagate
and corrode the tubes depending on the water quality, chemicals should
be fed to avoid such propagation.
3. If the storage period exceeds 2 months, water inside the chiller-heater
should be replaced. If the same water remains in the chiller-heater for
longer than 2 months, bacteria may propagate and corrode the tubes
depending on the environmental condition and water quality. Hence, the
chilled/hot water and cooling water pumps should be operated for a short
time and the water inside chiller-heater should be replaced at least once a
month.
4. If the storage period exceeds 6 months, apply pressure 1.5~3 PSI
(0.01~0.02 Mpa) with nitrogen inside the shells and leave as is. Internal-
pressure should be checked (at least once a week) to confirm that no
pressure drop occurs.
Cooling water line
Residential hot
water line
Inside of shells
Vacuum
Storage Period;
more than 2
months and less
than 6 months
Chilled/hot water
system
Filled with water
Cooling water
system
Residential hot
water line
Inside of shells
Vacuum
Storage Period;
more than 6
months
Chilled/hot water
system
Filled with water
Cooling water
system
Inside of shells
Pressurized with
Nitrogen (0.01~0.02
MpaG)
PART
STORAGE METHOD
NOTES
Storage Period;
less than 6
months
Chilled/hot water
system
Dried and pressurized
with Nitrogen
(1.5~3PSI
(0.01~0.02MPa(G)))
1. Chilled/hot water and cooling water systems should be drained completely
and dried by nitrogen blow, then pressurized with nitrogen and left as is.
Depending on the water quality, hard scale may be fixed on the inside
surface of tubes by drying and it can be removed only by chemical
cleaning. For more than 1 year’s storage, it is necessary to, after cleaning
the tubes, drain completely, dry up inside by nitrogen blow, then
pressurize with nitrogen and leave as is.
2. If the storage period exceeds 6 months, apply pressure 1.5~3 PSI
(0.01~0.02 Mpa) with nitrogen inside the shells and leave as is. Internal-
pressure should be checked (at least once a week) to confirm no pressure
drop occurs.
3. The manual valve on the purge piping should be fully closed.
Cooling water
system
Inside of shells
Vacuum
Storage Period;
more than 6
months
Chilled/hot water
system
Dried and pressurized
with Nitrogen
(1.5~3PSI
(0.01~0.02MPa(G)))
Cooling water
system
Inside of shells
Pressurized with
Nitrogen (1.5~3PSI
(0.01~0.02MPa(G)))
