TZ81DN - 80% Downflow Gas Furnace 


The Thermal Zone® 80% Downflow Furnace is a value-alternative which enjoys the benefits of high-efficiency at lower cost. 

  • Compact Cabinet
    With a cabinet height of just 34" for all capacities, space requirements are kept to a minimum and installations are easier.
  • Furnace Control
    This solid state integrated furnace control is the "brain" of this dependable furnace - controlling the blower and inducer motors for heating capacity and efficiency.
  • Patented Heat Exchanger
    Extremely compact the heat exchanger provides a faster, more efficient transfer of heat. The aluminized and stainless steel construction is so reliable, it’s backed with a 20 year limited warranty.
  • Induced Draft Blower
    It works specifically with the heat exchanger. The blower pulls hot combustion gases through the exchanger and vents them outdoors.
  • In-Shot Burners
    Regulated the air/gas mixture
  • Blower Motor
    An easy slide out blower motor for easy access. The blower quietly circulates air around the heat exchanger, where it is heated to comfortably warm your home.
  • Limited Warranty
    Twenty year heat exchanger limited warranty. All other parts have a five year limited warranty
ARI StandardC UL US Listed
80% AFUE
Heating Capacities from 50,000 to 150,000 BTU/HR