Dunham-Bush MM0305F, Руководство по установке, эксплуатации и обслуживанию

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3.0 INSTALLATION
FIGURE 3.13: REMOTE BULB
1. Remote Bulb Small Suction Line (Smaller Than 7/8” [22.2mm])
2. Remote Bulb On large Suction Line (7/8” [22.2mm] and Larger)
5.) For good thermal contact, the bulb should
be securely fastened with two bulb straps
to a clean, straight section of the suction
line. It should be insulated with cork tape
to prevent the effect of surrounding
environment.
3.14 EXTERNAL EQUALIZER
CONNECTION
The equalizer connection should be made at a
point that will most accurately reflect the
pressure existing in the suction line at the bulb
location. Generally, the connection is as close
to bulb on the downstream side.
3.15 HOT GAS BYPASS
The purpose of the hot gas by pass is to create
artificial load in the system by means of
injecting hot gas into the inlet of the
distributor. This would prevent the suction
pressure from falling below the desired
settings and thus causing frequent compressor
cycling. The valve is pressure actuated, where
it allows the discharge gas to bypass if the
downstream pressure is below the setting. The
setting could be changed by adjusting the stem
on the valve body. To set the pressure, loose
the seal nut as shown below and turn the
adjusting stem clockwise to raise the pressure
or counter clockwise to lower the pressure.
One turn of the stem equals to 16psig
[110.3kPa]. The adjustment range for the valve
is between 10”Hg [33.8kPa] to 120psig [827
kPa].
It is important that the setting to be performed
under actual operating condition, i.e. under
minimal system load conditions so that it could
maintain the minimum desired suction
pressure. Hot gas flow could be detected by
listening the gas flowing through the valve or
by touching the outlet pipe.
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