Performed 2 system cooling maintenance. I checked amps, capacitors, filters, drains, electrical connections, electrical components, cleanliness, and safeties. Recommendations 1. The upstairs unit has excessive dust build up on the blower wheel. This forces the motor to work harder to perform normal duties. This can result in premature failure. Suggest blower wheeling 2. Both outdoor units have oxidation present and slight build up in the coils. This reduces efficiency and makes the systems cost more to perform normal duties. Suggested chemical cleaning