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APOLLO AIR-TO-WATER SYSTEMS
APOLLO Heat Pump
Standard air-to-water hydronic heating & cooling
- Domestic hot water
- Fan coil heating & cooling
- Cold-climate operation down to -31°F
- Radiant floor heating
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HYDRONIC HEAT PUMP SYSTEMS
Air-to-Water Heat Pump Systems
Complete Comfort, Powered by Water
APOLLO heat pumps provide efficient heating, cooling, and domestic hot water through one flexible hydronic system, designed around your home, climate, and comfort needs.
Expert system sizing | Complete packages | Technical support from design to installation
HOW IT WORKS
How Hydronic Heat Pump Systems Work
An APOLLO air-to-water heat pump transfers energy between the outdoor air and a water-based system. Heated or chilled water can then serve radiant floors, fan coils, air handlers, domestic hot water, and optional pool heating.
Choose your heat pump
Two APOLLO Series. One Simple Choice.
The right APOLLO depends on your heating system and required water temperature. Standard APOLLO is the ideal choice for most homes, including cold-climate applications. Choose APOLLO MAX when baseboard heating, cast iron radiators, or other demanding systems require higher water temperatures, especially during very cold weather.
APOLLO MAX
APOLLO MAX Heat Pump
Higher water temperatures for demanding hydronic systems
- Baseboard heating
- Cast iron radiators
- Water temperatures up to 175°F (80°C)
- High-temperature output in extreme cold
Not sure which series fits? MBTEK confirms the right APOLLO heat pump for your emitters, climate, and water-temperature needs - just call or contact us.
System support
Need help planning the full system?
MBTEK can help match the heat pump, indoor equipment, tanks, controls, and system layout to your project.
HEATING, COOLING & HOT WATER
Build Your Complete APOLLO System
Choose the indoor equipment, tanks, controls, and distribution options that match your home and comfort needs.
DHW & water tanks
Domestic Hot Water and Buffer Tanks
APOLLO systems can be planned with domestic hot water tanks, stainless water tanks, or buffer tanks so one hydronic system can support home comfort and hot water needs.
Fan coils & air handlers
Heating and Cooling with Fan Coils
Fan coils and air handlers move warm or chilled water through indoor units, giving APOLLO systems a practical way to heat and cool rooms without traditional outdoor condensers at every zone.
Radiant floor heating
Radiant Floors and Manifold Stations
Radiant floors use warm water through PEX loops under the floor. A manifold station distributes water to each zone so rooms can be balanced and controlled more easily.
Hydro Smart Station
A Simpler Mechanical Room
The Hydro Smart Station helps organize the indoor side of an APOLLO system by combining key hydronic components into one compact station, reducing loose parts and installation labor.
Controls & schematics
Controls, Thermostats and Planning
MBTEK can help plan the system around thermostats, controls, wiring, equipment layout, and hydronic schematics so installers understand how each part connects.
Pool heating
Optional Pool Heating
Pool heating can be added to the hydronic plan when the right heat exchanger, controls, and sizing are selected for the pool and climate.
Use the Pool Calculator
Sizing help
What Size Air-to-Water Heat Pump Do You Need?
APOLLO models are available as a 3 ton, 3.5 ton, 4 ton, 5 ton, and 6 ton heat pump. These square-footage ranges are approximate — the right choice depends on building load, climate, insulation, and your hydronic system design, not square footage alone.
What affects final sizing?
- Square footage and layout
- Insulation level and air sealing
- Climate zone and winter design temperature
- Existing emitters: radiant floor, fan coils, radiators, or air handlers
- Heating load and cooling load
- Whether the system will also support cooling or domestic hot water
Series
Model
Approx. coverage
APOLLO
3.5 ton / 42k BTU
Up to 2,500 sq ft
APOLLO
5 ton / 60k BTU
2,500-4,000 sq ft
APOLLO
6 ton / 72k BTU
4,000-6,000 sq ft
APOLLO MAX
3 ton / 36k BTU
Up to 2,000 sq ft
APOLLO MAX
4 ton / 48k BTU
Up to 3,000 sq ft
APOLLO MAX
6 ton / 72k BTU
Up to 4,000 sq ft
Properties over 6,000 sq ft may need multiple heat pumps or a staged hydronic heat pump system.
BUYING GUIDE
Air-to-Water Heat Pump Buying Guide
Compare APOLLO products, understand sizing, and learn how a complete hydronic heating and cooling system works.
What is an air-to-water heat pump?
An air-to-water heat pump moves energy between outdoor air and a water-based hydronic system. Instead of sending heated or cooled air directly through ducts, it heats or chills water that can be distributed through radiant floors, fan coils, air handlers, buffer tanks, or domestic hot water equipment when the system is designed correctly.
How does an air-to-water heat pump system work?
The outdoor heat pump connects to the indoor hydronic system. In a complete APOLLO setup, the heat pump can work with the Hydro Smart Station, a buffer or water tank, and indoor comfort zones such as fan coils, radiant floors, domestic hot water, and optional pool heating.
What can an APOLLO system connect to?
APOLLO air-to-water systems can be planned around multiple hydronic applications, including radiant floor heating, wall-mounted fan coils, concealed fan coils, central air handlers, buffer tanks, indirect water tanks, thermostats, controls, and distribution components.
What size air-to-water heat pump do you need?
The right size depends on the building's heating and cooling load, insulation, climate, square footage, emitters, and whether the system is expected to support heating, cooling, domestic hot water, or pool heating. MBTEK offers 3.5 ton, 5 ton, and 6 ton APOLLO models for different project needs.
Is it right for your home?
An air-to-water heat pump is a strong fit when you want hydronic comfort, radiant floor heating, cooling through fan coils, or a complete heating and cooling system with equipment support before the sale. It is especially useful for projects where the goal is to build one integrated system instead of separate heating, cooling, and hot water solutions.
An air-to-water heat pump may be a good fit if you want:
- Hydronic heating with radiant floors, fan coils, or air handlers
- Heating and cooling from one water-based system
- Domestic hot water support with the right tank and system design
- A complete package including heat pump, Hydro Smart Station, tank, controls, and accessories
- Expert help choosing the right model before you buy
FAQ
Air-to-Water Heat Pump Questions
What is an air-to-water heat pump?
An air-to-water heat pump transfers energy between outdoor air and water. The heated or chilled water can then be used in a hydronic system for radiant floors, fan coils, air handlers, buffer tanks, or domestic hot water equipment when properly designed.
Can an air-to-water heat pump provide cooling?
Yes. With the right system design, an air-to-water heat pump can provide cooling by sending chilled water to compatible indoor equipment such as fan coils or air handlers. Radiant floors are usually used mainly for heating, while fan coils are better suited for cooling and dehumidification.
Can an air-to-water heat pump work with radiant floors?
Yes. Radiant floor heating is one of the most common hydronic applications for air-to-water heat pumps. The system sends heated water through tubing installed under the floor to provide even, comfortable heat.
Can an air-to-water heat pump work with fan coils?
Yes. Fan coils can use hot or chilled water from the heat pump system to provide room-by-room heating and cooling. They are often used when a project needs both heating and air conditioning from a hydronic system.
Can it support domestic hot water?
An air-to-water heat pump can support domestic hot water when paired with the correct tank, controls, and system design. The exact setup depends on the project requirements and selected equipment.
What kind of water tank do I need with an APOLLO heat pump?
Most APOLLO systems are paired with a DHW indirect water tank for domestic hot water heating. Buffer tanks are added in specific configurations — typically when the system needs more water volume, hydraulic separation between the heat pump and distribution circuits, or cycle protection in low-load conditions. The right tank setup depends on the project layout and system goals. MBTEK can help confirm the correct configuration before purchase.
What size air-to-water heat pump do I need?
Sizing depends on the building's heating load, cooling load, climate, insulation, square footage, and the type of indoor distribution used. MBTEK offers 3.5 ton, 5 ton, and 6 ton APOLLO models, but the right choice should be based on the actual project requirements.
Is an air-to-water heat pump good for cold climates?
Air-to-water heat pumps can be used in cold climates when the system is designed correctly. For more demanding cold-climate projects, MBTEK can help determine whether a standard APOLLO model or an APOLLO MAX model is the better fit.
Can an air-to-water heat pump heat a pool?
Yes, pool heating can be part of a hydronic system when the correct heat exchanger, controls, and system design are used. Pool heating should be planned as an optional application, not assumed by default.
How much does an air-to-water heat pump system cost?
The total cost depends on the heat pump size, Hydro Smart Station, tank, indoor distribution, accessories, controls, and installation requirements. The best way to estimate the system cost is to choose the main equipment and confirm the project layout with a specialist.
What is the difference between a DHW tank and a buffer tank?
A DHW indirect tank stores domestic hot water for household use, heating it through a heat exchanger connected to the heat pump loop. A buffer tank adds water volume to the system loop itself — it does not store domestic hot water. Some hydronic systems use both: a DHW tank for hot water and a buffer tank on the heating and cooling distribution side. MBTEK can help determine which combination fits your project.
