L.B. White’s Therma Grow heaters are the only heaters that have been certified to greenhouse requirements and emission standards.This heater offers 20% better fuel efficiency than other heaters with advanced, clean burning technology. The Therma Grow heater is completely enclosed to protect the working components, allowing it to be mounted either inside or outside of the greenhouse to maximize growing space. The 220 Plus model has two-stage capabilities for temperature, heating and air circulation control, to be effective in short cold spurts, or long winter months.

The Therma Grow 220 Plus offers all the enhanced specifications of the 120 Plus with the more power to heat your largest greenhouse. All 220 Plus models have two different heat settings at 120,000 or 220,000 BTU/hr, circulating the air output at 1,750 CFM. The 220 Plus is the most efficient and most powerful option; perfect for growers looking to maximize their heating capability.

L.B. White upholds a 10-year warranty against corrosion of the  heat chamber and case, leaving the grower with  low maintenance and repair costs for years.

Therma Grow Features:


  • 115 or 230 volts electric
  • Starting/continuous amps: 17/7 or 6.7/2.6 depending on voltage
  • Can be ordered to work with propane or natural gas
  • High-efficiency, reduces energy costs
  • Quick response time and dependable ignition
  • Meets OSHA greenhouse requirements
  • 10 year manufacturer’s warranty on heat chamber and case
Weight 150 lbs
Dimensions 35.5 × 25.5 × 30 in