Ok I'm stumped and could really use your help.
This just in
One my techs just called he is on a roof top working on a 25 ton ICP
PGE series.
The customer was cutting concrete Lots of concrete inside the building. They did not turn off the unit

and when they got cold they pulled the filter and tapped them out reinstalled and (do you see where this is going) now the coil is plugged with concrete dust. well when they saw what they had done they tried to clean the coil with water IT IS 7 Degrees here.
My Tech thawed the coil and now... how do you remove concrete from an evaporator coil (did i mention we installed this unit two months ago)
Any Ideas would be great I like this customer and do not want to R&R the coil.