Yes, fuel conversion factors can be used to compare different types of warm air systems, such as gas-fired furnaces, oil-fired furnaces, and heat pumps. By understanding the energy efficiency and conversion factors of each system, you can determine which system is most suitable for your specific needs and budget. For example, if you’re considering a gas-fired furnace with an AFUE rating of 90% and a heat pump with a COP of 3.5, you can use the conversion factors to compare the energy efficiency and cost savings of each system.