Acson international ADB100D, Manual

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25
CHARGING RECOMMENDATIONS
Charging liquid in a CONTROLLED manner into the suction side until the system is full
. This recommen-
dation does not hold true for reciprocating compressors where liquid charging into the suction side could cause
severe damage.
Carefully monitor the suction and discharge pressures - ensure that the suction pressure does not fall below 25
psig (1.7 bar) at any time during the charging process.
CAUTION : Manifold Gauge will show cylinder pressure rather than suction pressure if the cylinder valve and
Manifold valve "A" are both open.
There are many ways of charging liquid in a "controlled manner" into the
suction side:-
1. Use valve A on the manifold gauge set
2. Use the valve on the refrigerant cylinder
3. Charge through a Shredder valve
4. Use a hose with a Shredder valve depressor
5. Charge into the suction side at some distance from the compressor.
6. All of the above
The fundamental procedure is the same as for single phase models but the compressor can run in the wrong
direction on starting. If this happens reverse any two phases and start again. Short term reverse rotation will not
damage the compressor.
As compressors get larger the importance of correct field charging procedures grows exponentially. Unfortu-
nately larger systems are often field charged which leads to many infant failures. All Specter compressors have
internal discharge temperature protectors which are very effective in preventing dangerously high discharge
temperatures during charging. The protection module will trip and lock the compressor out for 30 minutes. It is
not normally necessary to wait 30 minutes for the module to reset. When the compressor has cooled down the
module can be reset by breaking the power supply to the control circuit. Very often the serviceman does not
understand why the module tripped and uses a jumper wire to bypass it. He continues to charge the system and
removes the jumper when charging is complete. The compressor may or may not run with the protector back in
the circuit but it is certain that the compressor has been damaged and premature failure is inevitable.
Charging Cylinder on Scale Close-up of Scale
A
Charging Procedures - Three phase compressors