AReCoS

Heat pump products

All-season heat pumps

For decades, frost has stopped heat pumps from heating. AReCoS heat pumps are designed not to: all-electric and dual-fuel prototypes, designed to keep heating through frost, with one patented controller in each unit and no cloud in the control path.

  • Controller: U.S. Patent 12,768,557, under test in a research agreement (CRADA) with UT-Battelle, LLC, which manages Oak Ridge National Laboratory for the U.S. Department of Energy
  • Air–water heat exchanger: patent pending
  • Patent and CRADA record
Reserve a place in the first units

Products

Three heat pumps, one heat exchanger and one controller.

  • Rooftop heat pump

    Up to 10 tons. All-electric with optional electric backup, or dual-fuel with a gas heat section.

    Prototype · pilots targeted for 2027

    See the rooftop unit How dual-fuel switches

  • Residential heat pump

    Up to 5 tons. All-electric, or with the home’s gas furnace. Ground-ready.

    Prototype · pilots targeted for late 2027

    See the home unit

  • EV heat pump

    Heat pump and controller for pilots; control software licensed for production.

    Pilots targeted for summer–fall 2028

    See the EV heat pump

What is different

One controller, designed to optimize the whole unit and set every actuator at once.

It is designed to run a physics model of the whole refrigerant cycle on the unit itself. No cloud.

Patent pending

Hardware

Air–water heat exchanger, with a new electromechanical way to remove frost while it heats

How it clears frost. Details under NDA: request the technical brief. U.S. provisional application 63/989,941.

Patent issued

Controller

Embedded controller, designed to set every actuator together

U.S. Patent 12,768,557, issued October 20, 2026, from application 18/592,624. Its hardware test is published in US 2024/0295337 A1 (FIGS. 4–7).

The full record The patent at the USPTO

In the architecture of U.S. Patent 12,768,557, the controller is designed to estimate the states its sensors can't measure and to set the actuators together in real time.

Startup, changeover and shutdown Winter, without defrost stops How it finds faults Does it need a supervisor? The controller in full

Three stacked time plots from the AReCoS heat pump model. Top: the compressor stops and, minutes later, restarts. Middle: the motor-driven reversing valve moves from heating to cooling while the unit is stopped. Bottom: the indoor and outdoor coil pressures come together while it is at rest, then separate the other way round when it restarts in cooling.
One changeover on a 59 °F (15 °C) day, from the AReCoS heat pump model: the motor-driven reversing valve moves while the unit is at rest, then it restarts in cooling. Amber: heating. Gray: stopped. Blue: cooling. Read it in full.

  • Lower total power, and answers the grid

    Designed to set the compressor, valves, fans and pump together for the lowest total power, and to shed or add load when the grid asks.

  • Units share the load to cut peaks

    Designed to share the load and pick setpoints among themselves over BACnet, with no supervisory system.

  • Names the likely cause, for faster service

    Designed to name the likely cause and where to look, in every mode.

Control stays in the building

No cloud in the control path. The AReCoS cloud only watches.

Optimization designed to run in the units, with no remote command service.

Any command path from the internet, cloud or not, is a way in. AReCoS is designed to keep the optimizer, and every command, inside the units; the building network, BACnet link, software updates and remote maintenance still need securing, and the security page says how.

With a cloud-dependent setpoint optimizer

  • Setpoints changed from the internet
  • Units started and stopped remotely
  • A command path in from the internet
  • Cloud optimizing stops when the link drops
  • Moves setpoints, not how units run

With AReCoS

  • Every command designed to stay on site
  • Cloud optional, and it only monitors
  • Designed with no command path from the internet
  • Designed to keep optimizing with the internet down
  • Designed to set every actuator together

In October 2026, attackers remotely switched on defrost cycles in supermarket refrigeration controllers in France; about 700 supermarkets were affected, the French government said, and some stores threw away fresh and frozen food. No cloud service has been reported in that attack; the controllers were in the stores.

NIST warns that the risk of cyberattack on building controls increases significantly as they are joined to corporate networks and the cloud. What that means for your site.

Security and the ActWhy setpoints alone fall short

Sources: NIST, Tips & Tactics for Building Automation & Control System Cybersecurity, August 2026. Associated Press, Cyberattack targeting refrigeration systems hits 700 supermarkets, French government says, October 2026.

Let's talk.

Pilot sites for the AReCoS heat pump RTU, manufacturing partners for the first builds, the controller for your refrigeration system, or the EV heat pump for your vehicle program.

Email info@arecos.net
625 Kenmoor Ave SE, Suite 350
Grand Rapids, Michigan 49546