I have a home built in 1918 with oil fired hot water heat. It does not have a separate hot water heater - hot water comes off of the boiler. During the summer the hot water was more than sufficient. Since the colder weather has arrived, the water coming out of the taps varies from cool to warm to hot. The oil contractor bled the radiators but that did not fix the problem. This is our first winter here so don't know if this problem occurred in the past. Any thoughts will be greatly appreciated.