Geothermal Heat Pumps

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How Geothermal Works

A geothermal heat pump works very similar to a conventional heat pump.  Instead of having the heat pump outdoors in your yard, the heat transfer happens outside under your yard.

Here in the Portland Oregon area, geothermal systems work very well, even though the temperature throughout the year varies.  We see everything from mild to 100 plus degree summers to cool frigid winters.  What you might not realize is that the temperature below ground stays fairly consistent all year.

heat transfer

Heating Mode

A conventional heat pumps capacity changes as the outdoor temperature drops, so it is harder to heat your home as it gets colder, and the system has to defrost itself ( turn into air-conditioning mode and run the back-up heat).

A geothermal system won’t see the drastic temperature swings because the coils are in the ground were the temperature is much more constant, and the unit won’t see the elements of the rain, snow sunlight etc.

Cooling Mode

An air conditioner sitting outside in the hot summer sun has to work very hard to transfer the heat from your home to outside.  A geothermal system takes the same heat from your home and transfers it into the nice cool ground. The amount of energy it takes to do that is much less, therefore saving you a lot of money!

Installing a Geothermal system in Portland

Although the upfront cost are more than a conventional heating and cooling system, Water Furnace geo­thermal systems are so energy efficient that in most cases the payback period is very short.  A study by the Air Force Institute of Technology calculated that it takes on average just seven to eight years to recoup costs on most geothermal systems.  The actual break even depends on the type of ground loop and the type/size of heat pump system, minus any rebates from local utilities and tax credits from the state and federal governments.

geothermal products

Earth Loops

Three Basic Geothermal Energy Sources

Closed-loop systems circulate a water-based solution through a "loop system" of small-diameter, high-density polyethylene underground pipes.  Closed-loop systems can be installed horizontally, vertically or in a pond.  Open-loop systems use an existing water well or surface water.  Whether the system is open or closed, heat is transferred to or from the structure, regardless of outdoor temperature, to provide year-round comfort.

geothermal loops

Horizontal Loops

Often used when adequate land surface is available.  Depending on geothermal system needs and space available, pipes are placed in trenches that range in length from 100 to 400 feet.

description of geothermal cooling

Vertical Loops

The ideal choice for a geothermal heat pump when available land surface is limited.  Well drilling equipment is used to bore small-diameter holes from 100 to 400 feet deep.

how does geothermal work

Pond (Lake) Loops

Very economical to install when a large body of water is available for use by the geothermal heating and cooling system.  Coils of pipe are simply placed on the bottom of the pond or lake to capture the geothermal energy.

what is geothermal system

Open loops (Well-Water Systems)

In ideal conditions, an open-loop application can be the most economical type of geothermal system.  These use groundwater from a well as a direct energy source.

Benefits of Geothermal

WaterFurnace geothermal heating and cooling products are among the most efficient, energy saving, environmentally conscience heat pumps you can purchase.  They are a natural heat pump that will give you years of reliable, safe home comfort at a low cost.

Lower Operating Cost

A WaterFurnace geothermal heat pump system operates more efficiently than ordinary heating and air conditioning systems because it can deliver an astounding five units of energy for every one unit of electrical energy used.  By combining stored earth energy with safe electric power, many WaterFurnace owners realize savings up to 70% for heating, cooling, and hot water.

Enhanced Comfort

Our geothermal systems provide precise distribution of comfortable air all year long, eliminating hot spots and cold spots.  During heating, you'll experience warm air without the hot blasts associated with ordinary gas furnaces, or the cooler air of an air source heat pump.  Additionally, when cooling, our geothermal units deliver cool, dehumidified air.


Unlike ordinary air conditioners or heat pumps, there is no noisy outdoor unit to disturb your outdoor environment or your neighbors.  WaterFurnace units are designed and constructed for "whisper quiet" operation, similar to your refrigerator.


Unlike air conditioners and heat pumps, geothermal units are installed indoors (like your refrigerator), so they are not subject to wear and tear caused by rain, snow, ice, debris, extreme temperatures or vandalism.  Geothermal units have proven to be very reliable and require less maintenance.

Environmentally Friendly

According to the Department of Energy and the EPA, geothermal systems are the most environmentally friendly way to heat and cool your home.  Our systems emit no carbon dioxide, carbon monoxide or other greenhouse gases, which are considered to be major contributors to environmental air pollution.  They are truly a natural, green heat pump.

Please contact us today for a free in home consultation to see if a Water Furnace geothermal system is right for you.