28 year old residential gas furnace won't light, problem solved
This furnace won't start. The main limit has tripped, and the board is in lockout. First thing was turn off power. Then change filter. The motor and capacitor were tested. Capacitor was low. While it was off the flame sensor and pressure tube were cleaned. Power on and lockout is gone. Furnace is working again. Sometimes the board is bad but not today. 28 years and still heating. The furnace tries to come on but it won't light The furnace flames come on but the blower doesn't The blower runs constantly but no heat The flames come on but go right out The thermostat clicks on but the furnace never starts The thermostat clicks on but the air conditioner won't start The fan comes on but its not cooling The fan on a/c isn't spinning The air conditioner is buzzing and won't come on The a/c makes a loud noise but doesn't start The ac has a humming but not coming on The air conditioner is running but not cooling