Default heat/cool amount declared as a property to be used in HeaterCoolerBack.options https://github.com/phetsims/scenery-phet/issues/423.
Default heat/cool amount declared as a property to be used in HeaterCoolerBack.options https://github.com/phetsims/scenery-phet/issues/423.

phetsims/scenery-phet,phetsims/scenery-phet,phetsims/scenery-phet