Frequently Asked Questions

Anyone with a refrigerator or an air conditioner has witnessed the operation of a heat pump, even though the term heat pump may be unfamiliar. All of these machines, rather than making heat, take existing heat and move it from a lower-temperature location to a higher-temperature location. Refrigerators and air conditioners are heat pumps that remove heat from colder interior spaces to warmer exterior spaces for cooling purposes. Heat pumps also move heat from a low-temperature source to a high-temperature space for heating.

An air-source heat pump, for example, extracts heat from outdoor air and pumps it indoors. A geothermal heat pump works the same way, except that its heat source is the warmth of the earth. The process of elevating low-temperature heat to over 100° F and transferring it indoors involves a cycle of evaporation, compression, condensation and expansion. A refrigerant is used as the heat-transfer medium which circulates within the heat pump. The cycle starts as the cold liquid refrigerant passes through a heat exchanger (evaporator) and absorbs heat from the low-temperature source (fluid from the ground loop). The refrigerant evaporates as heat is absorbed.

The gaseous refrigerant then passes through a compressor where the refrigerant is pressurized, raising its temperature to more than 180° F . The hot gas then circulates through a refrigerant-to-air heat exchanger where heat is removed and pumped into the building at about 100° F . When it loses the heat, the refrigerant changes back to a liquid. The liquid is cooled as it passes through an expansion valve and begins the process again. To work as an air conditioner, the system's flow is reversed.

No. There are different kinds of geothermal heat pumps designed for specific applications. Many geothermal heat pumps, for example, are intended for use only with higher temperature ground water encountered in open-loop systems. Others will operate at entering water temperatures as low as 25° F , which are possible in closed-loop systems. Most geothermal heat pumps provide summer air conditioning, but a few brands are designed only for winter heating. Geothermal heat pumps also can differ in the way they are designed. Self-contained units combine the blower, compressor, heat exchanger and coil in a single cabinet. Split systems (such as the WaterFurnace ES Split) allow the coil to be added to a forced-air furnace and utilize the existing blower.

• Ground & Air
• Milk straight from the cow and/or cooling system
• Rivers
• Streams
• Ponds
• Lakes
• Reservoirs
• Rain water harvesting
• Thermal springs
• IT rooms
• Plastic injection moulding
• Cooling plants
• Central refrigeration unit

• Any property 50m² - 2,100m² (500 - 22,000 sqft)
• Timber Frame houses
• Block houses
• ICF
• Passive
• Near passive
• Outdoor swimming pools
• Sea weed drying
• Swimming pools
• Sports complex
• Aquaculture
• Cheese dairy
• Radiators
• Underfloor heating
• Fan coils

The water requirement of a specific model is usually expressed in gallons per minute (g.p.m.) and is listed in the unit's specifications. Generally, the average system will use 1.5 g.p.m. per ton of capacity while operating, but the amount of water required depends on the size of the unit and the manufacturer's specifications. Your contractor should be able to provide this information. Your well and pump combination should be large enough to supply the water needed by the heat pump in addition to your domestic water requirements. You probably will need to enlarge your pressure tank or modify your plumbing to supply adequate water to the heat pump.

For every 1 unit of energy used to power your geothermal system, 4 units of heat energy are supplied. That’s about 400% efficient! Geothermal heat pumps can achieve this efficiency because they don’t create heat – they just transfer it. Only about one-third to one-fourth of the energy delivered in heating with a geothermal systems comes from electricity consumption. The rest is extracted from the ground. 

No. Geothermal systems are virtually maintenance free. When installed properly, the buried loop will last for generations. And the other half of the operation—the unit's fan, compressor and pump—is housed indoors, protected from the harsh weather conditions. Usually, periodic checks and filter changes are the only required maintenance. (Note: WaterFurnace has developed a geothermal unit—the ES Split—that is so rugged and quiet, it can be placed outdoors when that's the best solution).

Trenches are normally four to six feet deep and up to 400 feet long, depending on the number of pipes in a trench. One advantage of a horizontal loop system is being able to lay the trenches according to the shape of the land. As a rule of thumb, 500-600 feet of pipe is required per ton of system capacity. A well-insulated 2,000-square-foot home would need about a three-ton system with 1,500-1,800 feet of pipe.

Independent studies have proven that heat pumps are cheaper and more efficient than fuel oil, gas, and wood pellet heating. However, attention to detail on the installation is crucial to keeping running costs down.

• Limitless kW - Unlimited heat available in the ground and air
• Economical – Provides operating cost savings of 30% to 60% over conventional oil / gas
• Comfortable - Maintains an even temperature and humidity level when used in conjunction with underfloor heating
• Safe – No open flames, fumes or exhausts
• Environmentally Friendly – Our systems emit no carbon dioxide, carbon monoxide or other greenhouse gases
• Flexible – A single Heat Pump can handle heating, cooling and hot water up to 60°C (Some go up to 70°C)
• Lifespan – Air Source can last up to 15 years approx. and Geothermal up to 20 years approx.
• Value – Increases the value of your home and lowers energy bills
• Efficiency – As much as 5 times as efficient as conventional systems
• Low Running Costs – e.g. to heat a 2500 sq ft house for as little as €600 per year (BER rating of B1)
• Range - Units available for all sizes of dwellings, new and existing
• BER - Improves your Building Energy Rating (BER)

Main types of Heat Sources

Closed Horizontal Loop

Horizontal loops are often considered when adequate land surface is available. Pipes are placed in trenches in lengths that range from 30m to 70m and at a min depth of 1m.

Closed Vertical Loop

Vertical loops are an option when land surface available is limited. Well drilling equipment is used to bore 150mm diameter holes from depths of 60 – 120m

Pond / Lake

Pond/Lake Loops are economical to install when a body of water is available because excavation costs are eliminated. Coils of pipe are placed at the bottom of a lake.

Open Loop

Open Loop systems utilize ground water as a direct energy source. In ideal conditions, an open loop application is the most economical type of geothermal system. Although predominantly used for commercial or farm applications these can be economically used where the water table is high.