My AC unit, installed 1977, has a
precast pad under it. The AC unit is a
Carrier round unit and the pad is also
round. Maybe you can get a precast
pad and slide it under the unit. Or,
they do have 2' x 2' precast patio block
that are only 1 1/4" thick or there
abouts. Four of these might work.

Phisherman wrote:
On Fri, 8 Sep 2006 21:45:10 -0400, "miamicuse"
wrote:

My central AC compressor unit is outdoor resting on a concrete pad. The pad
is 48"x48" in size and 4" thick and it is reinforced with steel rod. I
snip

Thanks,

MC

Maybe you can wait until the A/C unit needs to be replaced? If need
be you can slide a 4x4 sheet of 3/4" thick external ply under the
unit.