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My Brand New Furnace Is Not Giving Me More Heat!!

My Brand New Furnace Is Not Giving Me More Heat!!

True or false?

I just had a brand new boiler or furnace installed in my home so I should have more heat in my house.

This is false in many cases.

But what if I had a much larger boiler or furnace installed in my home, wouldn't this give me more heat in my home?

In most cases this is also false; you will not have more heat even with a new boiler or furnace with a higher BTU output.

WHY NOT!!!? I just spent a small fortune on a brand new boiler or furnace and I was expecting more heat, not only did I not get more heat, I got less heat. I feel like I have been cheated.

I have had this discussion with a number of home owners in my many years of servicing and replacing residential boilers and furnaces. In many of the furnace and boiler replacements, the reason for replacing the boiler or furnace was inefficiency, meaning the boiler or furnace was burning more fuel then it needed to provide the heat needed to heat the home. Other reasons for replacing an old furnace or boiler are, a boiler or furnace is in such disrepair, it is more cost effective to replace then repair.

Rarely does a home owner say to me I want to replace my boiler because I do not get enough heat, it's kind of a thought in the back of the homeowners mind , assuming (Like I would, if I did not know better) A new boiler is going to put out more heat and heat the home better.

A new furnace will be more efficient and save you money on you fuel bills but will not make sections of your home warmer than the old boiler did.

This is why, the boiler is the heart of the heating system, the radiators and the baseboard are the arteries, the boiler makes the heat and pumps it through the radiators or baseboard pipes. Each radiator has a specific BTU output, meaning it will put out X amount of heat at a boiler water temperature of 180 degrees F, the same is true of baseboard heaters, on average 1 foot of Slant Finn Number 15 heating baseboard puts out 590 BTUs so 10 feet of Slant Finn baseboard will put out 5,900 BTUs at 180 degrees F. if the temperature is raised to 190 degrees F. the same baseboard will put out 610 BTUs per foot. Please note: it is not a good idea to have the boiler temperature above 210 degrees F. and most plumbers set new boilers at 180. So the boiler or furnace has nothing to do with the heating of the area, this is done by the baseboard or the radiators. If your home has a room or section of the home that never reaches the setting of the thermostat on really cold days, it's most likely not the boiler or furnace, it's the lack of or under sized radiators or baseboard in that area being heated. The solution to this problem may be the upgrading of windows in the rooms and increasing the insulation in the rooms, increasing the amount of baseboard or replacing baseboard with a higher output baseboard will help but better windows and insulation should be the first step.

The reason you may feel you are getting less heat from your new furnace is, most plumbers set the new boilers aquastat at 180 degrees F. if the old boilers aquastat was defective or set at 210 degrees F. it will put out less heat then the old boiler.

I said at the beginning in most cases this is false but in some cases a foolish inexperienced want to be plumber will install a boiler too small for the home, in a case like this the boiler cannot heat the water fast enough to pump it through the home at the required temperature. One way to detect a boiler being too small is it will run all day and night and never shut off, all boilers cycle on and off all day when it is very cold outside but the burner does go on and off throughout the day, if the burner never goes off, the boiler is too small.