I have 6 Ton Geocomfort unit installed last summer. Compressor sweats so much that there is puddles of water in the pan under it.Is this normal? Looks like pan will start to rust soon, it has some spots that show starting of rust.

 

It is not uncommon to have some moisture puddle around a heat pump compressor.
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Perhaps a dehumidifier in the basement will help minimize the problem? After all isn't sweating the direct result of too much moister in the air?

This could be caused by moisture in the air which could be managed more effectively by simply utilizing a small return register to the unit in the mechanical area or basement. This could be added to the section of return duct (drop) right next to the unit. In more extreme humidity cases and warmer climates an ERV (energy recovery ventilator) would be a better option (HRV - heat recovery ventilators would be used in colder climates). The construction of newer homes allows for very little outside air exchange which means the humidity which enters through indoor use is not exchanged to the outside air. If unaddressed this problem can continue to increase the humidity levels in the home. A stand alone dehumidifier is an option, but is limited in the area it will dehumidify.

1. Return Grille w/ damper installed in general area of unit
2. ERV, HRV, or Whole House Dehumidifier

Also, there could be some operational issues you are having with the system which would be causing the compressor to become colder than normal. This would have to be corrected by a technician during routine maintenance or your specific service request. The same technician could start eliminating moisture in the area by adding the return grille. If the problem still persists, it could then be evaluated whether to use a HRV, ERV, or whole house dehumidifier.

You can also insulate anything that is sweating.

Compressor Blankets are available as an accessory for the GeoComfort systems. This may be a minor fix for a bigger problem and the home and system should be evaluated by a technician.