What size infared heater do ineed to heat 1 big room of 2000 square feet?

Answer 1

That's going to depend on all of these other factors:

-- height of the ceiling in the room

-- are there rooms above or below the 2000-sq-ft room

-- how many of the walls in the room are outside walls

-- how many people are usually in the room when it needs to be heated

-- what the outside walls of the building are made of

-- what type of insulation the building walls have

-- the climate in which the building is located