Performed 1 system diagnostics: found that the outdoor unit was tripped on high pressure lockout. I checked the zoning. I replaced the air filter. I tested the emergency heat. I checked the blower motor and the capacitor and contactor on the outdoor unit. I found that the system is short on duct work and the bypass is too small. I also found biological growth on the indoor unit. I reset the system and ran it in AC mode (too hot to run in heat mode). I found that the system was reading low pressures probably due to it being low on air flow. The compressor is extremely loud and is near failure. I advised the homeowner about the biological growth, the system being low on duct work and the outside unit being impacted with dirt. With the homeowners permission I signed them up for the homecare and install a UV light to help prevent the biological growth from spreading. I removed some of the air handle insulation that had large amount of the biological growth on it and disposed of it. I coul