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Mitshubishi split muh-18nvand inside msh-18nv

After about 2hours running on cool unit stops cooling inside stays running fan only
I am an electrician
if any one can help to direct me to try solve problem will greatly appreciate it

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Re: mitshubishi split muh-18nvand inside msh-18nv

-Start the unit.
-Press EMERGENCY OPERATION switch.3-minute time delay works.Test run operation operates for 30 minutes.
-Check voltage to terminal block of outdoor unit.Is there 12V DC between 2-1?
-If voltage is presenet check the wiring, compressor contactor outdoor fan motor and compressor.
-If no voltage check voltage to terminal block of indoor unit.Is there 12V DC between 2-1?
-If if voltage is present re-connect the continuity of indoor and outdoor unit connection.
-If no voltage replace the indoor electronic control P.C.
-But also check the coil thermistor sensor and room air thermistor if this two is out of range it can cause the tripping of out door unit. It has the resistance of 8 to 10 k ohms at 25 deg c temp.

Posted on Jan 08, 2008

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