Looking for thoughts:
I'm a service tech and have a new Tempstar 14 SEER HP freezing up after @ 3 hrs. operation. New TXV installed.
Ambient: 75
Return DB: 71
Suction pressure: 55
Liquid pressure: 160
Temp drop: 20
Suction line temp: 40
Liquid line temp: 80

Also, unit would no pump refigerant ( R-22 ) back into unit with suction line closed when I installed TXV. Originally had #65 restrictor.
Can't figure why unit freezes up in cooling mode, except compressor is weak or there's some bypass somewhere.
Any help would be appreciated. Thanks.

Mike