Mitsubishi ms12tn mini split

You will need to check the head pressure, condensing temperature, sub cooling and superheat to determine this, but yes sounds as so or restricted.

I hope that you are using DUAL MANIFOLD guages to check this. I am not sure what you mean by drops out.

You have to let the system run for a while for the suction pressure to stabilize, if the metering device is a TXV pressure will rise and fall as the valve opens and closes. If this is R22 you need to get the suction pressure up

r we talking about a split system? begin pump down by closing the high side then watch as the suction drops to zero or very close u should here the compressor loading. turn off the compressor open low pressure port and see if the refrig. is being held by the valves. if the refrig flows back to air handler thru suction in a/c mode most lkely compressor needs to b replaced due to bad valves. also whats the twmp drop across the coil

There is small PCB in the AC, this PCB is malfuctioning also there is automatic ON /OFF switch Check whether ti is working properly or not.

oil pump, if it has never been replaced, its time already, also check seals inside the engine and gaskets

Sorry to sat but the tech has no idea what he is doing. The metering device is in the discharge valve, making that line a low pressure, not high. If the "suction" line is hotthen it is running in heat mode.

If this is running in A/C mode, then I bet you have a low refrigerant charge. The compressor is dropping out on low suction pressure if it's cutting in and out every 5-10 minutes or so. If it takes hours, then it's likely a different problem.

Reply back and I can help you (been in that business for over 30 years.).

disconnect the blower and turn on the ac.see if the coil frosts evenly.when you had the system open,you should have changed the liquid line drier.

The unit is restricted, reprocess the system, flush and vacuum it thoroughly.