I have a Blueline Bluewave the previous owner removed the heater core because it had a leak. He just connected the hoses together but since it had the water also being heated by the coolant of the machine it was still running about 180 degrees on the water temperature. I ran it like that for a while but got the heater core leak fixed and reinstalled it. It is now only getting to around 150 degrees. Why would this drop my water temperature?