The cable to the water valve that allows hot water from cooling system to circulate the heating part may be stuck or broken or the valve itself may be stuck. The cable may also have slipped and become too loose so it won't operate properly, last alternative is an air lock in the water system
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The cable to the water valve that allows hot water from cooling system to circulate the heating part may be stuck or broken or the valve itself may be stuck. The cable may also have slipped and become too loose so it won't operate properly, last alternative is an air lock in the water system