Lennox (NYSE: LII) is reporting that its joint venture with Ariston Group (Bloomberg: ARIS IM), formed in 2025, has completed its first year with residential water heater sales exceeding internal plans, according to a company statement.

The partnership introduced a line of residential gas, electric, and heat pump water heaters in North America during its first year. The products are designed to integrate with Lennox's existing distribution network and controls platform, and compatible systems can be managed through the Lennox Home Comfort app.

Water heater models feature heavy-gauge steel construction and a PermaClad glass lining. Select models include a SediMotion sediment-reduction system, FillSafe Protection for internal components, and Lennox Lock flammability protection.

"During the past year, we've entered the water heating category by prioritizing dealer training and integration with our existing distribution network and controls platform," said Sarah Martin, EVP and President of Lennox Home Comfort Solutions. "Early results have proven successful, and now we are focused on scaling distribution, expanding product availability, and increasing share across both HVAC and plumbing channels."

Ariston Group CEO Maurizio Brusadelli said the partners plan to continue investing in high-efficiency solutions for the North American market.

Lennox said its near-term priorities include expanding the number of store locations carrying water heaters, scaling distribution through its HVAC network, and continuing dealer training. The company noted that regulatory changes are expected to influence adoption of high-efficiency and heat pump water heaters.

Ariston Group, listed on Euronext Milan, reported €2.7 billion in revenues in 2025 and operates across 41 countries with 32 production sites.