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Heating, Air Conditioning, Fridge, HVAC/Baseboard Furnace Low Heat And Noise


My baseboard hot water furnace is making a humming/rushing noise when it fires up and prior to firing up and there is alot of banging of the pipes in the baseboard and there is reduced heat output,temperature of water will not go above 130 degrees.

Besides the low heat output of course,this noise is very annoying and can be heard throughout my small cape cod type house.


Of course it is difficult to know exactly without seeing the system in operation, but from the description my best estimate is there is air in the lines. There will be either manual or automatic air bleeds on the system. Usually there are a number of them depending on the size of the piping system, but the one to especially bleed will be at the highest point of the piping. I would bleed it with the system at full heat and do it several times at least an hour apart to allow other air in the piping to accumulate at this point. If you can locate all air bleeds, do each one. Air will not allow enough heat to infiltrate the water and you will get a low heat output and it will create a lot of noise in the piping. Thanks J

Heating, Air Conditioning, Fridge, HVAC

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J Cook


With 25+ years experience, I am familiar with residential, commercial, and industrial HVAC equipment including but not limited to boilers, chillers, reciprocating and screw compressors. I am trained in all manners of control wiring.


I currently have three HVAC licenses and Refrigeration license by the State of North Carolina. I have been in this field for over twenty years. I have been a service technician for a contractor and also worked at a state college in the repair and maintenance of steam lines and equipment. I am currently the Building Maintenance Superintendent for a municipality.

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