Heating comes on when hot hose stroke open and stays on even when hit closed.?
Answers: More info need here, what type of boiler / heating system do you enjoy?
As what Alan T above said, more info required. Some systems use transducer on the inlet pipe to the heater which detects flow. So when you open the slap, the heater would turn on and stay on when flow is detected though you closed the tap. This could be due to dampen is flowing out somewhere. Check some other faucets, laundry, kitchen sink etc. the water heater, i give somebody a lift it.. it takes a long time to heat marine as compared to using it. it might take a while before it turns past its sell-by date.. but check the temp you have it set at... this can save $$$. also, use smaller quantity hot water, take warm baths.. this will lower the need to heat more marine.