im in the field 3 years now and this is the first time ive come across this. residential split system 1.5 tons and i had a good suction pressure but my head pressure was super low, only 150-160. the strange thing is operations seemed pretty normal. cold suction line, warm liquid line, condenser was putting out good heat, good indoor air flow, clean filter clean coils. compressor is brand new. any feedback would be greatly appreciated as i am at a loss on this one.