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What is the difference between heating with a geothermal furnace vs a regular boiler that pulls from a well?

Shelly Gladwwell | Posted in General Questions on

The water is being pulled from deep in the ground then heated by gas to heat the water in the tubes. How would the Geothermal work if I still have to heat water that is pulled from deep in the ground now?

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  1. GBA Editor
    Martin Holladay | | #1

    If your house a conventional boiler that burns natural gas, propane, or fuel oil, there is water in the boiler and in the tubing (called hydronic tubing) that distributes the heat. That water can come from a drilled well or a municipal water service. Here's the key: the boiler is filled just once, on the first day the boiler is turned on. After that, it never needs water again (except a small amount occasionally to replace water that may have leaked).

    This is called a hydronic heating system. The heat comes from burning gas or oil.

    A geothermal system is more accurately called a ground-source heat pump. The heat pump that is at the heart of the system is similar to an air conditioner or the compressor in your refrigerator. It uses electricity as its fuel. The electricity operates the compressor.

    An open-loop ground-source heat pump circulates water from a deep well through the heat pump. The heat pump extracts some heat from the water, and returns the colder water back to the well. This type of system needs a lot of water circulating through the system whenever it is operating. It uses electricity to run a well pump as well as electricity to run the compressor. Most open-loop systems get their water from a drilled well.

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