I am using Roberts-Gordon Vantage II's
It is a radiant heat tube system powered by Nat Gas or Propane (mine is propane) I use two of them in the shop, the shop stared out @ 40x 88, so I bought them at 36 feet each (one in the paint room & one in the main part of the building. The building is now 56 X 88 & they still heat it very well. Radiant heat tubes heat the metal, cement, etc not the air & these are extremely efficient!!!!
My shop never gets below 55 degrees in the winter & my propane bills are dirt cheap!
God Bless
Bill
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