I am trying to check operating pressers on my home unit. The low side pressure on the R-22 scale reads 44. What should it read if ambient temp. is 89?

If you are a trained tech and have a license to handle refridgeant than you would know that answer... if you are not than I suggest you find one. The fines from the epa could be huge if there was an issue. Also one not knowing what they are doing can cause serious damage to themselves or the unit by trying to save a buck and do it themselves.