Competent with fluke and tools. Yearly routine last year was a bug in pressure switch 200 bucks later worked fine. Can't afford tech this year. Was heating 2 weeks ago worked fine. Today changed filter, killed power, pulled and cleaned pressure switch still NOT blowing cold air. What next please?

All motors working, compressor, condenser fan and blower motor?

Straight cool with gas heat or a heat pump?

Package or split system

if all motors (3) working can you feel the two copper pipes if a split system (http://www.thermal-medics.com/a-c-image-glossary/)

One duct blows only cold air when heater is turned on

All motors working.. gas.. pkg