Arrived on site to diagnose a that is making noise in furnace on a 2002 Intertherm Down flow system. Upon arrival spoke over with tenant and stated system dose work just every time system turns on system turns on really hard due to it’s condition and system click on sending power to all components and could hear motor it self consuming a lot of amps And working really hard to turn it on. Inspected indoor and out door unit. Inspected electrical compartment, Wiring, connections , and components. Inspected out door unit. Checked components and recorded readings of compressor and fan motor. The summary of finds are as followed. Furnace 1. 2002 down flow system. Furnace door cover dose not stay shut due to having broken tabs that clip in and hold cover shut. As they are using hook to just hold door from falling down. 2. Found sections of thermostat wires exposed from rats chewing it up. But since home has a big rat and rodent issue and crawl space under home is full of rat poop would