Your furnace or boiler should be

chosen considering :

• Size of the home
• Window types and  sizes
• Direction of house
• Neighbors
• Insulation
• Type of use and number of people
• Number your fans
• Living style
• Number of tenants
• Chimney condition
• Liner requirements
• Other gas appliances specially the water heater location and type
• Location of furnace room
• Location of vent termination
• And many more...