Hitachi Highly WHP13300PSD, Installation Manual

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H E A T P U M P W A T E R H E A T E R C O M P R E S S O R C R I T E R I A
热 泵 热 水 器 专 用 压 缩 机 使 用 基 准 PAGE：8/31
9 Dust of compressor hermetic terminals
Compressor hermetic terminals should be mounted with specified cover in right way to prevent
dust entering, and should be used in direction which dust is hard to enter in.
10 Lead wire of compressor hermetic terminals
Measuring the temperature of hermetic terminals , lead wire should be resist to the temperature
and be clamped so as not in touch with the surface of compressor and pipe.
11 Start-stop frequency
The frequency should be less than 6 times per hour. Operating time from start to stop should
be more than 3 minutes to make sure the oil is above the minimum level. Stopping time should be
more than 3 minutes to make sure the suction pressure and discharge pressure is balance.
12 Rate of rotational speed change
The rate of compressor rotational speed (acceleration) should be less than 133min
-1
/s as the
compressor speed is below 5400rpm while less than 60min
-1
/s as the compressor speed is higher than
5400rpm. However, when rotational speed is reduced to avoid temporary over-current， the rate
can also be less than 600min
-1
/s when the compressor speed is below 5400rpm and should be less
than 300min
-1
/s when the speed of compressor reach above 5400rpm，only if the variable range is
below 120min
-1
.
13 Air and moisture in refrigerating system
The degree of vacuum in refrigerating system should be less than 20Pa (150×10
－3
mmHg) at
room temperature just before charging refrigerant. The quantity of water should be less
than 0.15ml.