Geothermal Heat Pumps

A geothermal, or ground source, heat pump transfers energy between the earth and a hydronic water loop instead of exchanging heat with outdoor air.

Ground-loop fluid absorbs heat in winter and rejects it in summer. The heat pump transfers that energy to water serving the home's hydronic heating and cooling equipment.

An air-source heat pump exchanges heat with outdoor air, so capacity and efficiency drop as temperatures fall and the unit must run defrost cycles. A geothermal heat pump exchanges heat with the ground, which stays at a stable temperature year-round, so output stays consistent in any weather, there is no outdoor unit, and no defrost cycle is needed. Geothermal systems cost more to install because of the ground loop, but typically operate at higher seasonal efficiency.

A closed loop circulates a sealed water and antifreeze mixture through buried piping and is the most common choice. An open loop pumps water directly from a well or other source through the heat pump and discharges it, which can be very efficient where groundwater is plentiful and local codes allow it. APOLLO water-to-water heat pumps work with both configurations when the loop is designed correctly.

Horizontal loops are trenched a few feet below the frost line and suit properties with available land. Vertical loops use deep boreholes and fit smaller lots. Pond or lake loops submerge coils in a nearby body of water and can be the most economical option when one is available. The loop field is designed and installed locally; MBTEK helps confirm the heat pump and hydronic equipment that match it.

Because the ground is warmer than winter air and cooler than summer air, geothermal heat pumps typically deliver several units of heat for every unit of electricity they consume. Published water-loop heating COP for the standard APOLLO Geothermal reaches up to 6.7 on the 4 ton model under low-temperature water-loop conditions. The MAX series publishes water-loop heating COP up to 6.8 on the 4 ton and up to 5.9 on the 6 ton, with cooling COP 4.4.

Yes. Radiant floor heating is one of the best matches for a geothermal heat pump because floors run on low water temperatures, where the heat pump is most efficient. The system sends warm water through PEX tubing under the floor for even, comfortable heat.

Yes. The system supplies chilled water to compatible fan coils or air handlers for cooling and dehumidification; radiant floors are used mainly for heating.

Yes. With the correct indirect tank, controls, and system design, a geothermal heat pump can efficiently support domestic hot water.

APOLLO Geothermal and APOLLO Geothermal MAX are both offered in 4-ton (48k BTU) and 6-ton (72k BTU) models. Select the model from the building load, ground-loop capacity, and hydronic design.

The heat pump itself commonly lasts 20 to 25 years, longer than typical air-source equipment because it is installed indoors and protected from weather. A properly installed ground loop is buried infrastructure that can serve the home for 50 years or more.

Yes. Because the ground loop draws from stable underground temperatures rather than freezing air, a geothermal heat pump keeps its capacity in any climate, with no outdoor unit to ice up and no defrost cycle. That makes ground source systems a strong choice for the coldest regions of the United States and Canada.

Total project cost depends on the heat pump size and series, the ground loop type and installation, indoor distribution, tanks, controls, and accessories. The loop installation, whether vertical drilling, horizontal trenching, or a pond loop, is usually the largest variable. The best way to estimate cost is to choose the main equipment and confirm the layout with a specialist; incentive availability varies by state and utility, so check current programs.

Yes, pool heating can be part of the hydronic plan when the correct heat exchanger, controls, and system design are used. Pool heating should be planned as an optional application, not assumed by default.