hello a few days ago I asked why a friend had been told that the problem was the pump and the radiator I call them that because I am a plumber not a boilermaker when I saw the problem I suspected the water went down to the ceiling and the tank had a pressurizing pump that did not work and when the serve was all covered with tartar I put a nipple and everything was solved now I have a doubt thinking how a water heater works THE PASS WRENCH THAT ENTERS THE WATER OF THE TANK ONCE THE BOILER IS WALKING MUST BE CLOSED I think that in the water heater or hot water tank the water circulates but here it comes and it comes well I hope an answer thank you very much