I had a call on an American Standard GasPack 4 ton package unit. The unit was manufactured in 99. I found the unit had no freeon in it. I put nitrogen in it and leak checked it and found a crack between the 1/2 inch discharge line and a 1/4 inch line. After repairing it and evac and recharging the unit I noticed very excessive amounts of vibration in the unit. I changed the blower wheel and the evap side of the unit had much less vibration, so I went on my merry way. Three days later I had a call back on the unit, no freeon again. This time I found a leak on the high side schrader valve line inside of the cabinet. I repaired it, and rubberized the condenser fan connections on the unit totally isolating it. When I started up the unit I noticed the exhaust line still has an agressive vibration to it. The compressor was just changed out 11 months ago. Is there a possibility that the exhaust valve is bad or bent or something causing the vibration? If it is, is their something I can do to brace the exhaust line with metal and rubber to reduce the vibration to tollerable limits without changing out the compressor? This is my first major vibration problem and I could really use some help. One friend mentioned a stethescope as a tool? Is anybody out there? Help!
Any suggestions? Thanks, Mark M.