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Find every guide about a specific component.
Run Capacitor
Dual and single run capacitors on compressors and fan motors.
Contactor
The relay that sends line voltage to the compressor and outdoor fan.
Compressor
Scroll and reciprocating compressors: starting, windings and amps.
Condenser Fan Motor
PSC and ECM outdoor fan motors.
Evaporator Coil
Indoor coils: icing, dirt and pressure drop.
Metering Device (TXV, Piston, EEV)
TXVs, fixed orifices and electronic expansion valves.
Air Filter
Filter ratings, pressure drop and airflow problems.
Blower Motor
Indoor blowers: speed taps, ECMs and airflow.
Flame Sensor
Flame rectification, microamp readings and cleaning.
Igniter
Hot surface and spark igniters.
Gas Valve
Gas valve operation and gas pressure.
Control Board
Furnace and mini-split boards, fuses and LED codes.
Transformer
The 24-volt control transformer.
High Limit Switch
The furnace's overheat safety.
Pressure Switch
Proves the inducer is venting the furnace.
Inducer Motor
The draft inducer blower on gas furnaces.
Thermostat
Thermostat wiring, settings and placement.
Thermistor
Temperature sensors on mini-splits and heat pumps.
Inverter Board
Variable-speed drive boards in mini-splits and inverter systems.
Line Set
Refrigerant piping: length, flares and charge.
Reversing Valve
The valve that switches a heat pump between heating and cooling.