What is a “Radiator Cozy” and how does it work?

After larger infra­struc­tural inter­ven­tions proved unwork­able, the solu­tion for compli­ance at Inwood Park Apartments was installing radi­ator covers known as ​“Cozys.” 

Developed and manu­fac­tured by Kelvin, a company that special­izes in energy-effi­cient cooling and heating tech­nolo­gies, the Cozys are ​“ther­mo­static radi­ator enclo­sures” that offer insu­la­tion, as well as more precise temper­a­ture controls. 

The Cozy is a box fitted to the shape of a building’s cast-iron, base­board, or recessed radi­a­tors, explained Garrett Modeste, a repre­sen­ta­tive from Kelvin. The insu­lator contains a fan to blow out the heat from the radi­ator into the room, as well as temper­a­ture sensors to monitor the temper­a­ture inside the box and the ambient temper­a­ture of the room. 

Once each room has reached its desired temper­a­ture, excess heat remains trapped inside the Cozy. Then the network of ther­mome­ters built into the Cozys installed throughout the building digi­tally alerts the central boiler, which relaxes and cycles less often, or at a less high temper­a­ture. The result is less strain placed on central boilers — which creates energy savings for build­ings, and more temper­a­ture control for residents.

“When some­body says, ​‘I wanted it to be 72 degrees,’ [the fan inside] will kick on and start blowing the heat out of that enclo­sure until the room reaches the set point,” explained Modeste. 

Modeste cited a NYSERDA report finding that the Kelvin radi­ator Cozys have the capacity to reduce carbon emis­sions by an average of 25.5 percent for build­ings. At Inwood Park Apartments in partic­ular, the instal­la­tion of radi­ator cozies reduced the building’s carbon emis­sions by 27 percent.

In addi­tion to increasing a building’s energy effi­ciency, Cozys can offer partic­ular bene­fits to those residing in pre-war build­ings. For these complexes built between 1920 and 1949, the radi­ator covers help resolve prob­lems asso­ci­ated with inten­tional over­heating that was built into these radi­a­tors’ design.

The design of the Cozy allows tenants to regain a few inches of live­able space within their units — chil­dren and pets are protected from the heat of exposed radi­a­tors, and plants and fish tanks or terrar­iums have a comfort­able resting spot near sunlight. There is also an oppor­tu­nity to deco­rate and repaint the Cozy. 

Perhaps most impor­tant to Hal Fuchsman, the co-op board pres­i­dent of Inwood Park Apartments, is the data made avail­able by more precise temper­a­ture moni­toring. ​“Both [the] Cozy and the heat-timer system provide a wealth of real-time data, and insights that are already proving helpful as we think about our next steps.”