This question is in reference to a "King" brand natural gas floor furnace,Model number KF270, Serial number 6106, control number 2SMH, 70.000 BTU input and 49,000 BTU output. When the furnace comes on and warms the house to the desired temperature and goes off, it will not come back on unless you bump or jolt the valve sharply. Once the valve is jolted it comes on instantly and seems to work fine until it goes off and the you have to jolt the valve again to make it come on. Should I have the valve replaced or does it just need cleaning?

Should I have the valve replaced
Possibly, but first check electrical connections. These are low voltage, remove wires and sand ends. Make sure all connections are tight.

Thanks hkstroud.; I.ve checked the connections and all are good .When the thermostat is turned up you can hear a faint "click at the valve but it still does not turn the main burner on until you tap on the side of the powerpile valve operator .When the thermostat is lowered it turns the main burner off instantly.