I have regency C34 gas fireplace probably made around 2000. Unit has worked well but recently started itself and would not shut off until I shut the gas off. This has happen every time since when I relight the pilot light...it takes about 30 seconds and the main burner will ignite and not shut off until gas is turned off. Each time after I turn off the gas value in about 5 seconds I can hear something open/close not sure what. This unit has an thermostat remote control and a receiver box which runs on batteries that has an off, remote or on switch. I have removed the batteries from the remote, from the receiver even at different times and after I light the pilot in about 30 seconds the main burner ignites as mentioned above. I have moved the switch on the receiver box to off and the unit will not shut off. Please let me know what the problem could be.