Checking Compressor; Resistance Test - Daikin M Series Service And Troubleshooting

SERVICING
High Voltage
Connections
C L G N
1 2 3 4 5
Low Voltage Connections
EEM Motor Connections

Checking Compressor

Hermetic compressor electrical terminal venting can
be dangerous. When insulating material which supports
a hermetic compressor or electrical terminal suddenly
disintegrates due to physical abuse or as a result of an
electrical short between the terminal and the compressor
housing, the terminal may be expelled, venting the vapor and
liquid contents of the compressor housing and system.
If the compressor terminal PROTECTIVE COVER and
gasket (if required) are not properly in place and secured,
there is a remote possibility if a terminal vents, that the
vaporous and liquid discharge can be ignited, spouting
flames several feet, causing potentially severe or fatal
injury to anyone in its path.
This discharge can be ignited external to the compressor
if the terminal cover is not properly in place and if the
discharge impinges on a sufficient heat source.
Ignition of the discharge can also occur at the venting
terminal or inside the compressor, if there is sufficient
contaminant air present in the system and an electrical arc
occurs as the terminal vents.
Ignition cannot occur at the venting terminal without the
presence of contaminant air, and cannot occur externally
3/16"
1/4"
WARNING
from the venting terminal without the presence of an
external ignition source.
Therefore, proper evacuation of a hermetic system is
essential at the time of manufacture and during servicing.
To reduce the possibility of external ignition, all open
flame, electrical power, and other heat sources should be
extinguished or turned off prior to servicing a system.

Resistance Test

Each compressor is equipped with an internal overload.
The line break internal overload senses both motor
amperage and winding temperature. High motor
temperature or amperage heats the disc causing it to open,
breaking the common circuit within the compressor on
single phase units.
Heat generated within the compressor shell, usually due to
recycling of the motor, high amperage or insufficient gas to
cool the motor, is slow to dissipate. Allow at least three to
four hours for it to cool and reset, then retest.
Fuse, circuit breaker, ground fault protective device, etc.
has not tripped -
High Voltage!
Disconnect all power before servicing or
installing. Multiple power sources may be present.
Failure to do so may cause property damage,
personal injury or death.
1. Remove the leads from the compressor terminals.
See warnings before removing compressor terminal cover.
2. Using an ohmmeter, test continuity between
terminals S-R, C-R, and C-S.
WARNING
WARNING
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