System seems to be running great for a 7 year old unit checked all safety's , Blower wheel is clean, coil looks to be in good shape, drains are good, CST states they flush it with bleach every so often, I recommended the customer invest in pleaded filters instead of conventional , outdoor unit seems to be good, compressor is good, disconnect is good , delta is in good range , capacitor is up to tolerance overall this reem system is running great . CST got flyer by mail .