Quoted from mcluvin:Does it prevent the white crud buildup in the drain pan/line? I have to clean mine out twice a year or the drain line gets clogged.
It might help a little. That stuff is usually algae; unless your pan is made out of metal and it is corrosion? Most pans are plastic now for that reason, the plastic basically lasts forever. Either way, cleaning the pan and adding algae killer tablets or vinegar or even bleach keeps things running. Make sure you have a float switch in case things get out of hand it won't flood your house. On my old house I used to have to run vinegar through and if things got bad, I hooked up the shop vac to the drain pipe outside.
My new house I have annual maintenance on the unit and that included keeping the lines sucked out and adding algae killer. For $75 a year the onsite annual checkup and maintenance is a no brainer.