ClimaCool SHC onDEMAND 30, 50, 70, 85 Manual - Manual (Page 33)

31
www.climacoolcorp.com
‡ƒ–š Šƒ‰‡”•
Draining
When performing standard maintenance procedures such
ƒ•ƪ—•Š‹‰ƒŠ‡ƒ–‡š Šƒ‰‡”ǡ‹–™‹ŽŽ„‡‡ ‡••ƒ”›–‘‹•‘Žƒ–‡
either heat exchanger. This can easily be done with the
provided factory mounted water isolation valves. Access
–‘ƒƪ‘‘”†”ƒ‹‹•Š‡Ž’ˆ—Ž™Š‡’‡”ˆ‘”‹‰•–ƒ†ƒ”†
maintenance procedures.
Back Washing
It may become evident from the recorded weekly log data
that the performance of the chiller is gradually degrading.
This could be due to a buildup of debris or sludge
‘„•–”— –‹‰–Š‡ˆ”‡‡’ƒ••ƒ‰‡‘ˆƪ‘™–Š”‘—‰Š–Š‡Š‡ƒ–
exchangers. This debris can be removed by a back washing
process, which involves the introduction of a forced, violent,
„ƒ ™ƒ”†•ƪ‘™–Š”‘—‰Š–Š‡Š‡ƒ–‡š Šƒ‰‡”ǡ—•‹‰ƒ
ƒ”‡ˆ—ŽŽ›ˆ‘”—Žƒ–‡†ƪ—•Š‹‰•‘Ž—–‹‘Ǥ‘„‡‡ơ‡ –‹˜‡ǡ–Š‹•
„ƒ ƪ‘™•Š‘—Ž†„‡•Ž‹‰Š–Ž›Š‹‰Š‡”–Šƒ–Š‡‘”ƒŽƪ‘™ǡ
ƒ†‹–Š‡‘’’‘•‹–‡†‹”‡ –‹‘ǤŠ‡†‹ƥ —Ž–‹‡•ƒ†’”ƒ –‹ ƒŽ‹–›
of this method depends on the back wash pumping system
‹–•‡ŽˆǤ‘–Š‡”‡–Š‘†‹•–‘„ƒ ƪ—•Š‡ƒ ŠŠ‡ƒ–‡š Šƒ‰‡”
using city water instead of system water (see City Water
Cleaning Arrangement in Figure 13 on pg. 32). The back
washing procedure is accomplished by isolating each
individual heat exchanger and introducing the city water
—•‹‰ƒ ‘‡ –‹‘Š‘•‡–‘–Š‡Χdz•‡”˜‹ ‡’‘”––‘ƪ‘™‹
ƒ‘’’‘•‹–‡†‹”‡ –‹‘ˆ”‘–Š‡‘”ƒŽŠ‡ƒ–‡š Šƒ‰‡”ƪ‘™
direction. On the opposite ¾” service port, connect a drain
Š‘•‡–‘”—–‘ƒ•—‹–ƒ„Ž‡ƪ‘‘”†”ƒ‹Ǥ‘–‹—‡„ƒ ƪ‘™—–‹Ž
all debris is removed. ƒ”‹‰ǣƒ–‡”˜ƒŽ˜‡•—•–„‡”‡Ǧ
‘’‡‡†ƒˆ–‡”ƪ—•Š‹‰‹• ‘’Ž‡–‡Ǥ
Š‡‹ ƒŽŽ‡ƒ Žƒ ‡ƒ•Š‹‰‹–Šƒ–‡”
Isolation Valves
Chemical Clean in place washing will typically provide
the best debris removal, even from severely clogged
heat exchangers. It is only necessary to mechanically and
electrically isolate one chiller module at a time. The rest of
the chiller modules can continue to operate to satisfy the
cooling load required. The cleaning tank, pump and pump
strainer should be arranged in the manner shown in Figure
͕͘’‰Ǥ͖͗Ǧ Žƒ ‡Ž‡ƒ‹‰””ƒ‰‡‡–ǤŠ‡ƪ‘™‘ˆ–Š‡
Ž‡ƒ‹‰‹•ƒ””ƒ‰‡†‹–Š‡‘’’‘•‹–‡ƪ‘™–‘–Š‡‘”ƒŽ
operational direction. Connection points are provided using
the ¾” service ports at each heat exchanger. The cleaning
solution used can be either a detergent or hot water to
remove particles and simple cleaning. If correct water
treatment has been implemented, this should provide
adequate cleaning for most situations. The solution can be
pumped through the heat exchangers and allowed to soak
for a time and then pumped again.
If it is required to remove carbonates, then an acidic wash
should be used. A 2% solution of phosphoric or sulfamic
acids in pure water are generally acceptable. These acid
solutions should only be allowed to circulate within the heat
exchanger for 10 to 15 minutes, followed by a thorough pure
™ƒ–‡”ƪ—•Šˆ‘”͕͔–‘͕͙‹—–‡•ǤNo Hydrochloric or sulfuric
acids can be used. In any case, consult the chemical supplier
to establish the correct formulation and handling process.
The materials, which will be exposed to the wash, are stated
on page 16 – Water Treatment.
Once the washing is complete, the solution should be
ƪ—•Š‡†‘—– ‘’Ž‡–‡Ž›„›’—’‹‰ Ž‡ƒǡˆ”‡•Š™ƒ–‡”
through the chiller. To achieve a reasonable level of dilution,
it may be required to change the water several times.
After cleaning, the water quality and water treatment
•Š‘—Ž†„‡ ‘Ƥ”‡†Ǥ