Ethel Walker School

Ethel Walker School is located in Connecticut on a 175-acre campus sits amidst farms and meadows. For more than 100 years, The Ethel Walker School has been an all-girls school for grades 6–12 plus postgraduate education.   

This past summer Controlled Air, Inc. Worked with A.P. Construction to provide the HVAC portion of recent new building for a campus expansion. Controlled Air installed a Variable Refrigerant Flow System (VRF) system.   

The VRF system included 29 exhaust fans, 16 electric duct heaters, (4) cabinet unit heaters and six (6) electric unit heaters as well as one (1) 1.5-ton Lennox mini split heat pump system with low ambient and wall mounted indoor evaporator units with a programmable thermostat. We also installed Seven Lennox VRF outdoor heat recovery system  with Six (6) 16-ton outdoor heat pumps, two (2) 10-ton outdoor heat pumps, sixty-four (64) one-way indoor cassette units, five (5) compact 2x2 indoor cassette units, five (5) 3x3 indoor cassette units, one (1) high static ducted indoor unit, two (2) vertical air handler ducted indoor unit, and eight (8) outside air ducted air handler units.    

A new Johnson Controls FX-80 Supervisory front-end controller was installed with a Web-based user interface complete with enclosure and accessories. 85 touchscreen programmable controllers were also installed to allow for customized controls in each of the rooms.  

This extensive VRF system allows for individualized controls for all dorms and classrooms.  Lennox VRF systems allow for customized heating and cooling schedules. They can also operate in a wide range of temperatures, from -13°F (-25°C) for heating to 126°F (52°C) for cooling. Lennox VRF systems use heat recovery technology to move heat from areas that need cooling to areas that need heating, which can be an efficient way to condition spaces. The inverter-driven compressor can also reduce energy use by adjusting its speed based on demand from each indoor unit.      

Additionally, we furnished and installed two (2) Mitsubishi Water Source Heat pumps and two (2) corresponding heat exchangers for the domestic Hot water system, this included circulators, buffer tanks, storage tanks and an electric swing heater.