I was working on an Rheem rpne-048jaz r-22 condenser going out on low pressure lockout in heat mode. In cool mode, pressures are perfect. Here in Florida todays temp was about 70 and the pressures were about 65psi/170psi. In heat mode with the defrost board bypassed so I could watch pressures the high side dropped to 0psi and at the suction gauge port between compressor and reversing valve it drops to 0psi also. At the suction port at the service valve it sits at about 250psi. I replaced txv on condenser and it did nothing. I also removed filter drier outside the condenser and it also did nothing. I tested temps across the reversing valve when in cool and heat to see if the valve was shifting properly and it seems fine. My buddy says the condenser is like slugged out and the restriction is in the condenser coil. Its funny because when it runs in heat I could see the lines ice up at filter drier on the liquid line and the txv on the condenser ice up also and then thaw like the Freon was rushing into the condenser coil. Any info or advice would be great. I cant stop thinking about it. Thanks. Oh yeah I hope all this made some since.