A multifamily apartment complex in the Bronx, New York, has upgraded its domestic hot water system by replacing its gas boiler with a high-efficiency 95kW (27TR)-capacity CO2 (R744) heat pump.
The air-source Laars E-Therm unit, which delivers outlet water temperatures of around 170°F (77°C) and has a COP of 4, was installed at the 48-unit six-story building in support of the city’s electrification and decarbonization efforts.
“The installation of the Laars E-Therm is going to make a huge difference in the performance of this building,” said Francis Rodriguez, Weatherization Director at the Association for Energy Affordability (AEA), a nonprofit organization that supported the project. “We’ll achieve greater efficiency with less equipment.”
The installation sets a benchmark for future electrification upgrades in New York City’s residential sector, according to project partners. It offers a scalable and sustainable solution for multifamily buildings, they noted.
“We’re so happy with how this project went,” added Rodriguez. “We’ll most likely use this install as a prototype for all heat pump water heater installations going forward.”
While the new heat pump meets the building’s entire domestic hot water needs, the existing gas boiler remains in place as a backup, Dominic Danquah, Energy Engineer at AEA, told NaturalRefrigerants.com.
“We’ll most likely use this install as a prototype for all heat pump water heater installations going forward.”
Francis Rodriguez, Weatherization Director at AEA
Government policies
The AEA partnered with the South Bronx Community Organization and the Father Gigante organization to secure a grant through New York state’s Weatherization Assistance Program, which reduces heating and cooling costs through energy-conservation measures for low-income households.
Government policies like the recently amended 6 NYCRR Part 494, which has established GWP thresholds for refrigerants in various HVAC&R equipment, also have a role to play in supporting the state’s adoption of sustainable technologies, noted Danquah.
“Most of the projects – [either] new construction or [retrofit] projects – are mainly driven by regulations and the availability of funding incentives and not necessarily a desire of owners or developers to go electric,” he said.
Plug-and-play
The system comprises one Laars E-Therm plug-and-play CO2 heat pump unit, stratified storage tanks and a tank system control to supply residents with an efficient and reliable supply of hot water.
The heat pump is pre-charged with R744 refrigerant and features an integrated double-wall heat exchanger, streamlining installation, operation and maintenance, according to the AEA. By eliminating the need for a secondary glycol loop – often associated with added complexity and cost – this design also enhances system efficiency and reliability.
“The plug-and-play design made our lives much easier and will continue to do so for those performing maintenance,” said Rodriguez.
For larger projects, up to 16 Laars E-Therm units can be installed in cascade to supply capacities of up to 1.5MW (426.5TR).
