Former Apple Engineer Launches $3,800 Heat Pump That Installs in Under an Hour, Targeting California's Electrification Gap
Merino Energy debuts the Mono, a single-unit heat pump that plugs into a standard 120-volt outlet and costs roughly half the price of a conventional mini-split, as California races to install millions of heat pumps by 2030.
Overview
Merino Energy, a Bay Area startup founded by former Apple engineer Mary-Ann Rau, began taking pre-orders on April 7 for a compact heat pump that costs $3,800 installed and can be set up in under an hour. The product, called the Mono, consolidates the indoor and outdoor components of a traditional heat pump into a single wall-mounted unit roughly the size of a radiator, according to TechCrunch.
The launch comes as California pursues an ambitious target of six million heat pump installations by 2030, with only approximately 2.3 million currently in place. Merino’s approach bets that the biggest barrier to adoption is not consumer interest but the cost and complexity of installation.
What We Know
Rau, who previously worked on Apple’s AirPods and later at heat pump startup Quilt, co-founded Merino Energy with Brad Hall, a former director of mechanical engineering at Gradient, another window-unit heat pump company, according to TechCrunch. Rau has said the idea came after she received a $40,000 quote to install heat pumps in her San Francisco home, having already added solar panels, an induction stove, and an EV charger.
The Mono eliminates the external condenser found in conventional mini-split systems. Instead, it uses two wall vents for intake and exhaust, plus a condensate pipe, as its only exterior-facing elements. The refrigerant is factory-sealed, removing the need for on-site copper brazing or refrigerant charging — steps that typically require specialized HVAC technicians and add hours to installation time, as reported by TechCrunch.
At 7.8 inches deep, the unit is designed to fit beneath a window and runs on a standard 120-volt outlet, meaning most homeowners will not need electrical panel upgrades. The system includes Wi-Fi connectivity with occupancy sensing and supports Apple HomeKit and Google Home integration. Merino has also announced a planned integration with Oura Ring to adjust room temperature based on sleep cycles, according to TechCrunch.
The unit carries a SEER2 efficiency rating of 15.2. That is notably lower than premium mini-splits — Quilt’s two-zone system, for example, achieves a SEER2 of 25 — but Merino has explicitly traded peak efficiency for lower cost and simpler installation. At $3,800 including installation, the Mono undercuts typical mini-split systems, which Fast Company reports cost $4,000 to $6,000 per zone before factoring in full-day installation labor.
Merino has already completed a pilot deployment of 48 units at Civic Center Apartments, a low-income housing development in Richmond, California, for formerly homeless residents, according to TechCrunch. The company has signed up six installers across the Bay Area and Los Angeles. Deliveries are expected to begin later in 2026, with an initial focus on California before expansion to Hawaii, Oregon, and Washington.
“If we can reduce the amount of time and complexity of installing a heat pump, then we can scale adoption,” Rau told TechCrunch.
Industry Context
The residential heat pump market in the United States has grown steadily but remains a small fraction of overall HVAC installations. California’s target of six million units by 2030 would require roughly tripling the current installed base in under four years. The primary obstacles are well-documented: high upfront costs, complex multi-day installations, the need for electrical panel upgrades with 240-volt systems, and a shortage of trained installers.
Merino is not the only company attempting to solve these problems. Gradient, where co-founder Hall previously worked, offers a window-mounted heat pump. Quilt, where Rau previously worked, sells a higher-efficiency but more expensive ducted system. The broader market also includes efforts by major manufacturers like Mitsubishi, Daikin, and Carrier to reduce installation friction for conventional mini-splits.
At the industrial scale, the heat pump sector is also seeing new entrants. Advansor, a subsidiary of Dover Corporation, announced its SteelXL heat pump on April 8, a high-capacity CO2 unit with per-unit capacity of 5 megawatts and system capacity up to 50 megawatts, targeting food processing, district heating, and large commercial buildings, according to PR Newswire. The SteelXL can produce hot water at temperatures up to 203 degrees Fahrenheit and achieve a coefficient of performance of up to 4.0, positioning it as a replacement for gas and oil boilers in industrial settings.
What We Don’t Know
Merino has not disclosed its funding details or investors. The company’s ability to scale manufacturing and maintain the $3,800 price point as demand grows remains unproven. The SEER2 rating of 15.2, while adequate for California’s mild climate, raises questions about the Mono’s viability in colder regions — a factor that could limit the company’s expansion plans beyond the West Coast.
The pilot at Civic Center Apartments provides an early signal, but 48 units is a small sample. Long-term reliability data for the single-unit design, particularly the factory-sealed refrigerant system, is not yet available. Whether the simplified installation process translates into the kind of rapid deployment Merino envisions will depend on installer adoption and consumer willingness to accept the efficiency trade-off.
The broader question is whether products like the Mono can meaningfully accelerate heat pump adoption at the pace California’s targets demand, or whether the gap between 2.3 million and six million installations requires policy interventions — such as expanded rebates, stricter building codes, or gas hookup bans — that go beyond product innovation alone.