Choosing the right heater for a greenhouse depends on space, ventilation, fuel type, and energy efficiency. This guide highlights five gas or gas-assisted options along with electric alternatives that perform well in greenhouse environments. Each choice is evaluated for coverage area, venting options, and installation considerations to help growers maintain steady temperatures for healthy plant growth.
| Product | Brand | Type | BTU / Watts | Vent/Installation Notes |
|---|---|---|---|---|
| Mr. Heater F260560 Big Maxx MHU80NG | Mr. Heater | Natural Gas Unit Heater | 80,000 BTU | Category 1 vertical venting; 8 ft. clearance |
| Mr. Heater F260550 Big Maxx MHU50NG | Mr. Heater | Natural Gas Unit Heater | 50,000 BTU | Vertical/horizontal venting; outside access to thermostat and gas connections |
| ProCom MN300TBA-B | ProCom | Ventless Natural Gas Blue Flame | 30,000 BTU | Ventless; wall mount or base feet; thermostat control |
| ProCom MN100TBA-B | ProCom | Ventless Natural Gas Blue Flame | 10,000 BTU | Thermostat control; wall mount or base feet |
| Buyplus 1500W Greenhouse Heater | Buyplus | Electric with Thermostat | 1500 Watts | Digital thermostat; overheat protection; suitable for patios, greenhouses, and garages |
Mr. Heater Big Maxx MHU80NG (80,000 BTU)
The Mr. Heater F260560 Big Maxx MHU80NG is a natural gas unit heater designed for larger greenhouse spaces with an 80,000 BTU output. It supports vertical venting and requires a minimum clearance of 8 feet from the floor to the base. The unit is intended for natural gas and includes mounting brackets and a conversion kit for propane as optional accessories. Heater dimensions are 29.33 inches in length, 15.50 inches in width, and 26.37 inches in height. This model is suitable for spaces up to approximately 2,000 square feet, offering robust heat delivery for extended cold periods.
Key considerations: ensure proper venting, electrical supply for ignition, and compliance with local safety codes. Regular maintenance of gas lines and venting is recommended to maintain efficient performance.
Mr. Heater Big Maxx MHU50NG (50,000 BTU)
The Mr. Heater F260550 Big Maxx MHU50NG provides 50,000 BTU for mid-sized greenhouses, featuring flexible venting options with easy outside access to thermostat and gas connections. This unit is versatile for vertical or horizontal venting and is designed to be practical where space is moderate. It supports efficient heat distribution while allowing straightforward installation and serviceability. Consider pairing with an appropriate venting plan and a qualified technician for safe operation.
ProCom MN300TBA-B Ventless Natural Gas Blue Flame
The ProCom MN300TBA-B is a ventless blue flame space heater rated at 30,000 BTU. It is designed for indoor use in living spaces, offices, or greenhouse areas without external venting, though ventless operation may require careful room sizing and ventilation considerations. It includes thermostat control and can be wall-mounted or placed on the floor with base feet. This unit is well-suited for zones where venting options are limited or where quick heat delivery is needed.
ProCom MN100TBA-B Ventless Natural Gas Blue Flame
The ProCom MN100TBA-B offers 10,000 BTU and ventless operation with thermostat control, ideal for smaller greenhouse zones or auxiliary heat in a grow space. It provides a compact footprint suitable for wall mounting or floor placement with included base feet. While compact, ensure adequate ventilation and CO safety considerations when using ventless gas heaters in greenhouse environments.
Buyplus Greenhouse Heater with Digital Thermostat
The Buyplus heater delivers 1500W of electric heat for greenhouse spaces up to about 215 square feet. It includes a digital thermostat with a waterproof temperature probe and adjustable heating range from 40°F to 108°F. The unit features overheat protection and is versatile for outdoor, garage, or grow tent use. This provides a quiet, efficient alternative when gas availability or venting is a concern.
Buying Guide: Key Purchase Considerations
- Heat output vs. space: Match BTU or wattage to the greenhouse size. Overheating can stress plants and waste energy; under-heating reduces growth rate.
- Fuel type and venting: Natural gas units require venting and proper gas supply; ventless gas heaters are convenient but require sufficient room ventilation and CO checks. Electric heaters avoid combustion byproducts but depend on electrical availability and safety.
- Ventilation and safety: Ensure proper installation clearances, venting materials, carbon monoxide detectors, and adherence to local codes. For vented gas heaters, choose appropriate venting orientation (vertical/horizontal) and clearance to combustibles.
- Control and automation: Thermostats and digital controls improve precision. Look for thermostats that maintain setpoints and include safety features like overheat protection.
- Durability and maintenance: Choose units with corrosion-resistant components and accessible service parts. Regular inspection of gas lines, venting, and electrical connections extends equipment life.
- Energy efficiency: In longer grow seasons, higher-efficiency units reduce operating costs. Consider temperature zoning to heat only active areas of the greenhouse.
- Mobility and installation: For portable or modular setups, select models with straightforward mounting options or wheels and brackets for flexible layouts.