First, do you know who installed your system the first time around? Is the dispensing tower an actual "glycol" tower? How long of a run are the lines from the walk-in cooler to the tower?
When you indicated blend gas, was this mixed gas in a cylinder or did the technician install a gas blender? What is the temperature of the existing glycol system, beer in kegs, pressure against the kegs, types of beers?
This is a start. In order to assist you, we need to know as much as possible about the variables of the system and that may tell us if you should even continue with your existing tech.
Scott Zuhse, Instructor
Micro Matic Dispense Institute