Yamato Scientific WS220 Water Purifiers - Manual (Page 18)

14
Handling Precautions
CAUTION!
Prevention of freezing
If it is necessary to use this unit at a cold place in winter, and if the pipe or the water in the boiler
could freeze, install an electric lamp (100 - 200W) in the armor of the main unit to prevent
freezing. Such lamp to prevent freezing and this unit shall always be energized by different
power sources. Such lamp must not be energized via the breaker in this unit.
Using well water
If any well water is used for the raw water, more of residues including scale are deposited in the
boiler. Therefore, clean the inside of the boiler more often than the case tap water is used.
Characteristics of distilled water
Distilled water has the following characteristics. However, it is ideal to use the demineralized
water immediately after it is distilled and sampled. If, therefore, distilled water has been pooled
in the tank for a long time, drain such water once, and then start distillation anew. Substances
of low boiling point such as ammonia can be removed, and both electrolytic and non-electrolytic
substances can be removed averagely as well. In the manufacturing (condensation and
storage) process, however, carbon dioxide gas is absorbed from the atmosphere to produce
carbonic acid. So the electric conductivity is worse than ion exchanged water; about 2 to 3 x
10
-4
S/m (2 to 3μS/cm) 25℃. This is a weak acidity (PH5 to 6). To remove the dissolved
gases (oxygen and carbon dioxide gas) in the demineralized water, see the item "2 - Common
Items, (8) Water" in JIS K 0102 (How to Test Industrial Waste Water).
Recovery of power failure
When power is supplied after a power failure, the device automatically starts operation again with
the same state as just before the power failure. It is danger that the device starts unattached
operation after a power failure. We recommend for you to turn off the switch of this unit if a
power failure occurs during operation.