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Q.1
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If
the superheat is abnormally high at the evaporator outlet, then
this must mean that the expansion valve is closed too tightly. |
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True |
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False |
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Q.2
|
A
three-phase 380/660V motor supplied by 3-phase 380V must be delta
(D) coupled. |
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True |
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False |
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Q.3
|
If
the external temperature is 27°C, then the water flowing through
a cooling tower can never be cooled to below this value. |
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True |
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False |
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Q.4
|
If
there is a voltage measured between the terminals of an electrical
contact, then this confirms that the contact is open. |
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True |
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False |
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Q.5
|
To
draw water from a depth of 20m, two surface pumps are often be installed
in side-by-side. |
|
True |
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False |
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Q.6
|
If
the bulb of a thermostatic expansion valve has been pierced, all
the refrigerant in the system will escape into the atmosphere. |
|
True |
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False |
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Q.7
|
Pre-expansion
in the liquid line is more likely to occur when the evaporator is
located at a lower level than that of the liquid receiver. |
|
True |
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False |
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Q.8
|
With
R12 transitional replacement blends, the liquid temperature gradually
increases as it moves through the evaporator. |
|
True |
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False |
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Q.9
|
In
order to replace a blocked capillary expansion valve, all you need
to know is its length and external diameter. |
|
True |
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False |
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Q.10
|
Using
a dry cooler results in a lower HP than using a cooling tower. |
|
True |
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False |
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Q.11
|
In
order to assist the return to normal freezing conditions after defrosting,
it is recommended that both a MOP expansion valve and a start-up
valve are used. |
|
True |
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False |
|
|
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Q.12
|
If
the flow of water through pipe-work is doubled, the pressure drop
in the pipe-work is also doubled. |
|
True |
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False |
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|
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|
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Q.13
|
An
excessively low LP, a high superheat and low sub-cooling are typical
signs of a lack of refrigerant charge in a system. |
|
True |
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False |
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|
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Q.14
|
The
greater the difference between the ambient temperature and the evaporating
temperature in a cold room, the higher the humidity. |
|
True |
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False |
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|
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Q.15
|
In
a reversible heat pump, a small difference between the HP and LP
can result in seizure of the 4-way cycle inversion valve. |
|
True |
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False |
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Q.16
|
When
the liquid outlet valve is closed, it is quite normal for the HP
to increase while compressor pump-down is underway. |
|
True |
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False |
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Q.17
|
In
a closed system, it is generally best to install an expansion vessel
under nitrogen pressure at the pump discharge. |
|
True |
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False |
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Q.18
|
If
the refrigerant liquid temperature is 30°C at the condenser outlet,
then sub-cooling can be assumed to be adequate. |
|
True |
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False |
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Q.19
|
A
2-speed Dahlander type motor has a terminal box containing 6 terminals.
|
|
True |
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False |
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Q.20
|
If
a chilled water pump is rotating in reverse, Delta T for the water
at the evaporator increases. |
|
True |
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False |
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