My space heater is very much a problem last winter I had no trouble with warming the down stairs and up stairs with comfort now that summer past and winter comes my heater does not blow out enough heat to so much as warm up one room. Hope you can help me what causes heat loss? Thanks!

Is it the same space heater? Have you followed the maintenance protocols for this unit? Is it a unit that requires a new sock-like wick every once in a while? Did you clean it right between seasons? Have you changed anything..like did you cover all windows with plastic last year and not this year?

Bill, you need to provide more information before anyone can answer with any degree of helpfulness. Is it a kerosene heater, gas, electric ? The fact that you mention it 'blowing' suggests that it is at least equipped with a fan or blower, but it would help if we knew what kind of heating element it contains. Can you provide the rating in BTUs, or Watts, etc.? To go from heating two floors (of what size house) to a single room suggests a major change of some sort.