- Trane and American Standard 824:
Compatible with the conventional 24 volt cooling, heating, heat pump and dual fuel forced air systems. - Trane and American Standard 850:
Compatible with conventional 24 volt cooling, heating and heat pump dual fuel systems when used with a relay panel. Also compatible with Trane and American Standard Communicating and Variable Speed systems. - Trane and American Standard 950:
Compatible with conventional 24 volt cooling, heating and heat pump dual fuel systems when used with a relay panel. Also compatible with Trane and American Standard Communicating and Variable Speed systems. Provides control for a zoned system.