Maxx Ice MIM1000, Руководство по обслуживанию

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Compressor Check
Compressor and Start Components
The compressor should run during the entire cycle. If the machine is in the ON position but the
compressor is not running, check the compressor contactor to see if it is engaged. If the contactor is
not engaged, the problem is not with the compressor or the compressor start components. If the
contactor is engaged and there is correct voltage through the contactor, there could be a problem
with one of the starting components or the compressor. It is recommended that the compressor
starting components be replaced when replacing a compressor.
DISCONNECT POWER BEFORE SERVICING!
If the compressor uses an internal overload, be certain that the compressor has cooled and the
overload has reset before diagnosing the compressor. If the compressor is cool and is still not
running, check the compressor motor windings by first removing the wires at the compressor
terminals. With an ohmmeter, check for continuity between all three terminals, if an open circuit
exists between any of the terminals, the compressor may need to be replaced. Check for continuity
from each terminal to the compressor body, if continuity is found from any terminal to the
compressor body, the compressor windings are shorted to ground and the compressor will need to
be replaced. If the compressor appears to be good at this point, it is advisable to use a compressor
analyzer to isolate the compressor from the start components while checking for a locked rotor. If
an analyzer is not available, the compressor starting components must be checked.
If all starting components are good, check the amperage draw from the common terminal of the
compressor, making sure proper voltage is supplied to the compressor and all wiring is properly
connected. If the compressor does not start and there is excessive amperage draw, (see locked rotor
amps on compressor tag) the compressor has a locked rotor and should be replaced.
Overload (External)
If there is no amperage draw check the compressor overload. The compressor overload can be
checked for continuity after removing it from the compressor and letting it cool to room
temperature. If there is no continuity between the two terminals, replace the overload. If the
overload is suspected of opening prematurely, it should be replaced with an overload, which is
known to be good.
Capacitors
The start capacitor is an electrical storage device used to provide starting torque to the compressor.
If a start capacitor is defective, the compressor will not start properly. The run capacitor is an
electrical storage device used to improve the running characteristics and efficiency of the
compressor. Before checking a capacitor, it should be discharged by shorting across the terminals.
If a run or start capacitor is cracked, leaking or bulging it should be replaced. If a capacitor is
suspected of being defective, it can easily be checked by replacing it with a capacitor of the correct
size, which is known to be good. If the compressor starts and runs properly, replace the original
capacitor. A capacitor tester can also be used.
Start Relay
The start relay breaks the electrical circuit to the start windings when the compressor motor speed
increases. If the relay is defective, the compressor will not start or it may start but will run for a very
short time.
A compressor relay can be checked by removing the relay and checking the relay contacts for
damage and check for continuity across the closed relay points. Check the relay coil with an
ohmmeter. If no continuity is read, replace the relay.
Other Components