When selecting the best propane greenhouse heater for backup use, reliability and safety are key. The VEVOR Propane Heater stands out for its adjustable BTU range and portable design, making it a versatile choice. The Mr. Heater Big Buddy PRO Series offers high heat output suitable for larger spaces, while the Mr. Heater 9000 BTU Portable Buddy balances portability with efficient heating. The main tradeoffs involve balancing size, heat capacity, and safety features. Continue reading for a detailed comparison that will help you choose the right backup heater for your greenhouse.
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Key Takeaways
- High BTU capacity models like Mr. Heater Big Buddy PRO are better suited for larger or colder greenhouses but can be bulkier and more expensive.
- Portability varies significantly; smaller units like Mr. Heater Little Buddy are easy to move but may lack the power needed for larger spaces.
- Safety features such as auto-shutoff and ventilation are common in higher-end models and crucial for backup use.
- Adjustable heat settings provide flexibility, but simpler models may lack this feature, making temperature control less precise.
- Ventless options like the Mr. Heater vent-free heater simplify setup but require proper ventilation considerations for safe indoor use.
| propane greenhouse heater for backup use | Safety features | BTU |
|---|---|---|
| VEVOR Propane Heater | — | — |
| Mr. Heater Big Buddy PRO Serie | — | — |
| Mr. Heater 9000 BTU Portable B | Tip-over, low oxygen shut-off | 3,800 |
| Propane Heater Indoor and Outd | ODS & Tip-over | — |
| Mr. Heater Little Buddy Portab | Tip-over, low oxygen shut-off | 3,800 |
| ProCom Heating Liquid Propane | Oxygen Depletion Sensor (ODS) | 10,000 |
| LAANPOLE 15000BTU Propane Heat | Auto-Shutoff, Tip-Over Protection | 15,000 |
| Mr. Heater 18,000 BTU Vent-Fre | Low oxygen shut-off | 18,000 |
More Details on Our Top Picks
VEVOR Propane Heater, 6000 to 18000 BTU, Portable Gas Radiator for Indoor/Outdoor Use
[grimfaste asin=”B0FFXWF5L1″ mode=”image” alt=”VEVOR Propane Heater, 6000 to 18000 BTU, Portable Gas Radiator for Indoor/Outdoor Use” image=”https://m.media-amazon.com/images/I/81Ou70OqKlL._AC_SY300_SX300_QL70_ML2_.jpg” link=”0″]Best Overall Backup Propane Heater
View Latest PriceThis model stands out for its flexibility, offering adjustable heat settings from 6,000 to 18,000 BTU, making it suitable for a range of backup scenarios where space size and heating needs vary. Compared to the Mr. Heater Little Buddy, it covers a much larger area—up to 450 sq.ft.—yet remains portable thanks to locking wheels. Its safety features, including low oxygen, tip-over, and flameout protections, are essential for backup use, especially in enclosed spaces. The main tradeoff is that it depends on a propane tank and may not be sufficient for very large spaces or extended periods without refueling. This pick makes the most sense for users who need a versatile, portable heater capable of handling different backup situations reliably, but who are aware of safety and capacity limits.
Pros:- Adjustable heat settings for tailored comfort
- Multiple safety protections for secure operation
- Portable with locking wheels for easy relocation
Cons:- Requires a propane tank, adding to setup complexity
- Limited to 450 sq.ft, not suitable for larger spaces
- Heats effectively only when used properly with safety precautions
Best for: Homeowners needing a flexible, portable backup heater for indoor or outdoor use in spaces up to 450 sq.ft.
Not ideal for: Large commercial greenhouses or spaces requiring continuous, high-capacity heating over several days without refueling.
- BTU Range:6000 to 18000 BTU
- Heating Area:450 sq.ft
- Fuel Type:Propane
- Tank Capacity:20 lbs
- Run Time:up to 73 hours
- Dimensions:1.82 sq.ft
- Protection Features:Low oxygen, tip-over, flameout
- Altitude Compatibility:up to 4921 ft
Our verdict“This heater is a versatile, portable choice for backup heating in small to medium spaces, balancing safety and capacity.”
Mr. Heater Big Buddy PRO Series Heater
[grimfaste asin=”B0002WRHE8″ mode=”image” alt=”Mr. Heater Big Buddy PRO Series Heater” image=”https://m.media-amazon.com/images/I/81fRu1n5+9L._AC_SY300_SX300_QL70_FMwebp_.jpg” link=”0″]Best for Extended Backup Use
View Latest PriceThe Big Buddy PRO is designed for continuous use, providing a steady 18,000 BTU output suitable for spaces up to 450 sq.ft., and offering a dual heating system that combines radiant and convection heat. Compared with the VEVOR heater, it includes a built-in high-powered fan, which improves air circulation and comfort during longer backup periods. Its long runtime—up to 216 hours on two 20lb tanks—makes it ideal for sustained backup needs, but it does require propane tanks and an optional hose, adding to the setup complexity. This model is better suited for users who want dependable, long-duration backup heating without frequent refueling, but it’s less portable than smaller options.
Pros:- Long runtime on two propane tanks
- Combines radiant and convection heat for comfort
- Built-in fan improves air circulation
Cons:- Requires propane tanks and extra setup with hoses
- Less portable due to size and tank requirements
- Potentially voids warranty if unauthorized accessories are used
Best for: Home users seeking reliable, long-term backup heating for spaces up to 450 sq.ft. with extended runtime.
Not ideal for: Users needing a lightweight, highly portable heater for short-term or emergency outdoor use only.
- Heating Capacity:18,000 BTU
- Coverage Area:450 sq.ft
- Heat Settings:Low, Medium, High
- Run Time:216 hours on two 20lb tanks
Our verdict“This heater is best suited for those who prioritize long-lasting, reliable backup heating over portability.”
Mr. Heater 9000 BTU Portable Buddy Radiant Propane Heater
[grimfaste asin=”B002G51BZU” mode=”image” alt=”Mr. Heater 9000 BTU Portable Buddy Radiant Propane Heater” image=”https://m.media-amazon.com/images/I/716pv-cuKWL._AC_SY300_SX300_QL70_FMwebp_.jpg” link=”0″]Best for Small Backup Spaces
View Latest PriceThis compact heater provides 9,000 BTU, making it well-suited for small backup scenarios such as garages or workshops up to 225 sq.ft. Unlike larger models, it emphasizes portability and ease of use, powered by a small 1 lb propane cylinder that offers several hours of heat—perfect for quick, short-term backup needs. Its safety features, including an emergency low oxygen system, are standard, but the limited heating capacity means it’s not appropriate for larger areas. Compared with the VEVOR or Big Buddy models, it sacrifices capacity for portability, making it ideal for users who need a lightweight, portable solution for small spaces during outages or emergencies.
Pros:- Highly portable and lightweight
- Quiet, odor-free operation
- Safety features include tip-over and low oxygen shut-off
Cons:- Limited to small areas up to 95 sq.ft.
- Relies on small 1 lb propane cylinders, requiring frequent refills
- Not suitable for prolonged heating of large spaces
Best for: Individuals needing a portable, small-space backup heater for garages, tents, or small workshops.
Not ideal for: Larger greenhouses or spaces requiring sustained heat over several days with higher BTU needs.
- BTU:3,800
- Heats up to:95 sq ft
- Fuel:Propane
- Stand size:8 inches
- Ignition:One button
- Safety features:Tip-over, low oxygen shut-off
Our verdict“This heater excels as a portable, small-space backup solution for quick, emergency heating needs, but isn’t designed for large or continuous use.”
Propane Heater Indoor and Outdoor, 18,000 BTU Patio Heater with Safety Features
[grimfaste asin=”B0FH6N2FTH” mode=”image” alt=”Propane Heater Indoor and Outdoor, 18,000 BTU Patio Heater with Safety Features” image=”https://m.media-amazon.com/images/I/71PP4dyMRgL._AC_SY300_SX300_QL70_FMwebp_.jpg” link=”0″]Best No-Electricity Backup Heater
View Latest PriceThis heater offers 18,000 BTU of adjustable heat, capable of warming outdoor or indoor spaces up to 450 sq.ft., with the notable advantage of requiring no electricity—making it ideal during power outages. Its safety features, including oxygen depletion and tip-over protections, match those of the VEVOR heater but with added convenience of Piezoelectric ignition. Compared to the Mr. Heater Big Buddy PRO, it is less suitable for long-term continuous use but excels in ease of operation and mobility. Its main tradeoffs are the need for a 20lb propane tank and the necessity to operate only in well-ventilated areas, limiting indoor use in tightly sealed spaces.
Pros:- No electricity needed, great during outages
- Adjustable heat settings for flexibility
- Safety features for secure operation
Cons:- Requires a 20lb propane cylinder
- Limited to outdoor or ventilated indoor use
- Potential safety concerns if used improperly indoors
Best for: Users seeking a reliable, no-electricity backup heater for outdoor patios or well-ventilated indoor areas during outages.
Not ideal for: Enclosed spaces without good ventilation or users needing a heater for large, continuous indoor heating over days.
- Heating Power:18,000 BTU
- Coverage Area:450 sq ft
- Heating Modes:High/Medium/Low
- Run Time:up to 69 hours
- Safety Features:ODS & Tip-over
- Fuel Type:Propane
Our verdict“This heater provides dependable, electricity-free backup heat for outdoor or ventilated indoor spaces, with safety precautions in mind.”
Mr. Heater Little Buddy Portable Radiant Propane Heater
[grimfaste asin=”B001CFRF7I” mode=”image” alt=”Mr. Heater Little Buddy Portable Radiant Propane Heater” image=”https://m.media-amazon.com/images/I/71USYoPyuAL._AC_SY300_SX300_QL70_ML2_.jpg” link=”0″]Best Compact Personal Backup Heater
View Latest PriceThis small heater outputs 3,800 BTU, heating areas up to just 95 sq.ft., but its compact size makes it ideal for personal or small-space backup needs. It features simple one-button ignition and safety shut-offs, ensuring easy operation in emergencies. Compared with larger units like the VEVOR or Big Buddy, it sacrifices capacity for portability and convenience, making it perfect for tents, small workshops, or emergency kits. Its limited heating area means it’s not suitable for larger spaces or prolonged use in cold conditions, but for quick, portable backup heating, it performs well.
Pros:- Extremely portable and space-efficient
- Quiet, odor-free operation
- Simple, one-button ignition
Cons:- Limited to small areas up to 95 sq.ft.
- Requires a propane cylinder, which needs frequent refills
- Not suitable for long-term or large-space heating
Best for: Individuals needing a portable, lightweight backup heater for small rooms, tents, or personal spaces.
Not ideal for: Large greenhouses or spaces requiring sustained heat over hours or days.
- BTU:3,800
- Heats up to:95 sq ft
- Fuel:Propane
- Stand size:8 inches
- Ignition:One button
- Safety features:Tip-over, low oxygen shut-off
Our verdict“This heater is perfect for quick, portable backup heat in small spaces but isn’t designed for extensive or prolonged use.”
ProCom Heating Liquid Propane Ventless Blue Flame Heater with Base Feet – 10,000 BTU, Thermostat Control
[grimfaste asin=”B0CD1SSDTS” mode=”image” alt=”ProCom Heating Liquid Propane Ventless Blue Flame Heater with Base Feet – 10,000 BTU, Thermostat Control” image=”https://m.media-amazon.com/images/I/71w7kw6Io3L._AC_SY300_SX300_QL70_FMwebp_.jpg” link=”0″]Best Compact Indoor Backup Heater
View Latest PriceThis heater stands out for its efficient indoor performance and sleek, modern design, making it ideal for backup heating during power outages. Unlike the Mr. Heater 18,000 BTU vent-free model, this unit is more space-efficient, but it offers slightly less heat output. Its thermostat control allows for steady temperature management, which is a plus over simple on/off models. The ventless design means no venting required, but it limits use to indoor spaces with good ventilation. While it provides reliable heat up to 500 sq. ft., it requires a propane supply and lacks remote control, which could be inconvenient for some users.
Pros:- Efficient heating up to 500 sq. ft., ideal for small to medium rooms
- No electricity required, perfect for power outages
- Modern, stylish design with versatile mounting options
- Built-in safety features like oxygen depletion sensor
Cons:- Requires a propane tank and external supply setup
- No remote control or advanced digital features
- Limited to indoor use only
Best for: Homeowners needing a stylish and reliable backup heater for indoor use during outages or cold spells.
Not ideal for: Large spaces or outdoor use, since its coverage is limited and it lacks weather resistance features.
- BTU:10,000
- Area Coverage:500 sq. ft.
- Fuel Type:Liquid Propane
- Control:Thermostat (High/Medium/Low)
- Safety Features:Oxygen Depletion Sensor (ODS)
- Mounting Options:Wall mount or floor with base feet
Our verdict“This unit suits those who want a compact, safe, and stylish backup heater for indoor spaces during outages but don’t need large-scale heating or remote controls.”
LAANPOLE 15000BTU Propane Heater with Auto-Shutoff & 3 Heat Settings
[grimfaste asin=”B0HBPJW1ZP” mode=”image” alt=”LAANPOLE 15000BTU Propane Heater with Auto-Shutoff & 3 Heat Settings” image=”https://m.media-amazon.com/images/I/71FYTiaYE+L._AC_SY300_SX300_QL70_FMwebp_.jpg” link=”0″]Best Versatile Outdoor/Indoor Portable Heater
View Latest PriceThis model shines for its higher heat output and adjustable settings, making it suitable for outdoor patios, garages, or well-ventilated indoor spaces. Compared with the Mr. Heater 18,000 BTU vent-free heater, the LAANPOLE provides more control with three heat settings and a portable design, though it sacrifices some indoor safety features for outdoor versatility. Its auto-shutoff and tip-over protection enhance safety, but it requires a propane cylinder, and safety concerns increase if features are disabled. Its durable aluminum construction ensures reliability in various environments, but it’s less suited for enclosed indoor spaces without proper ventilation.
Pros:- Powerful 15,000 BTU heating capacity with three adjustable settings
- Auto-shutoff and tip-over protection for enhanced safety
- Portable, lightweight, and durable for outdoor and indoor use
- Highly adjustable heat levels for different needs
Cons:- Requires a separate propane cylinder, which adds setup complexity
- Potential safety risks if safety features are disabled
- Limited indoor safety clearance without proper ventilation
Best for: Outdoor enthusiasts or homeowners needing a portable, adjustable heat source for patios, garages, or outdoor workshops.
Not ideal for: Small indoor spaces or environments where indoor air quality and safety are paramount, as it’s primarily designed for outdoor use.
- BTU:15,000
- Heat Settings:3 (Low/Medium/High)
- Safety Features:Auto-Shutoff, Tip-Over Protection
- Material:Heavy-duty aluminum
- Weight:Lightweight
- Use:Outdoor and indoor
Our verdict“This heater is a great choice for users who need a portable, adjustable propane heater for outdoor or ventilated indoor spaces with safety features for peace of mind.”
Mr. Heater 18,000 BTU Vent-Free Propane Radiant Heater
[grimfaste asin=”B01DPZ56J6″ mode=”image” alt=”Mr. Heater 18,000 BTU Vent-Free Propane Radiant Heater” image=”https://m.media-amazon.com/images/I/819jDrTxArL._AC_SY300_SX300_QL70_FMwebp_.jpg” link=”0″]Best Large Indoor Backup Heater
View Latest PriceThis heater offers robust indoor heating with up to 18,000 BTU, capable of warming larger spaces up to 700 sq. ft. It’s distinguished by its vent-free design, allowing installation in spaces where venting isn’t feasible, and its built-in thermostat provides precise temperature control. Compared to the ProCom model, it delivers more heat and coverage but requires a propane supply and safety considerations for indoor use. The electronic ignition and safety shut-off make it more convenient and safer than manual ignition options. However, the lack of included blower fan means some users might find the heat distribution uneven, and indoor safety measures must be strictly followed.
Pros:- High heat output of 18,000 BTU, suitable for large rooms
- Vented-free design allows flexible indoor installation
- Built-in thermostat for consistent temperature control
- No electricity needed for operation
Cons:- Requires a propane connection and proper safety procedures
- Blower fan kit sold separately, which may affect heat distribution
- Indoor safety considerations are critical to prevent oxygen depletion
Best for: Homeowners needing a high-capacity, vent-free heater for large indoor spaces during power outages.
Not ideal for: Small rooms or spaces with poor ventilation, due to safety and venting considerations.
- BTU:18,000
- Coverage:700 sq. ft.
- Fuel:Liquid Propane
- Venting:Vent-free
- Safety features:Low oxygen shut-off
Our verdict“This heater is ideal for those who need reliable, large-space indoor heating with minimal electrical dependency, provided safety protocols are followed.”
How We Picked
Products were evaluated based on a combination of performance, safety features, ease of use, build quality, and value for backup heating in a greenhouse setting. We prioritized models with reliable ignition, adjustable heat output, and safety features such as auto-shutoff or ventilation. The ranking also considers portability for ease of repositioning during power outages or emergencies, along with user-friendly controls. Our goal was to identify options that balance power, safety, and affordability to serve as dependable backup heaters for various greenhouse sizes and conditions.| propane greenhouse heater for backup use | Safety features |
|---|---|
| VEVOR Propane Heater | — |
| Mr. Heater Big Buddy PRO Serie | — |
| Mr. Heater 9000 BTU Portable B | Tip-over, low oxygen shut-off |
| Propane Heater Indoor and Outd | ODS & Tip-over |
| Mr. Heater Little Buddy Portab | Tip-over, low oxygen shut-off |
| ProCom Heating Liquid Propane | Oxygen Depletion Sensor (ODS) |
| LAANPOLE 15000BTU Propane Heat | Auto-Shutoff, Tip-Over Protection |
| Mr. Heater 18,000 BTU Vent-Fre | Low oxygen shut-off |
Factors to Consider When Choosing Best Propane Greenhouse Heater For Backup Use
Choosing the best propane greenhouse heater for backup use involves understanding several key factors. First, consider the heater’s BTU rating relative to your greenhouse size to ensure sufficient heat output. Safety features like auto-shutoff and ventilation are essential to prevent accidents, especially in enclosed spaces. Portability might matter if you need to move the heater easily during power outages or for seasonal adjustments. Additionally, evaluate the ease of use and maintenance requirements, as a simple, durable design can save time and hassle during emergencies. Lastly, budget and value should align with your specific needs, balancing initial cost against long-term reliability and safety.Size and BTU Output
Matching your heater’s BTU rating to your greenhouse size is critical. An underpowered unit won’t provide enough warmth during cold snaps, while an overly powerful heater may consume unnecessary fuel and pose safety risks. For backup use, it’s better to have a slightly higher capacity than you think you need, ensuring reliable heat during extreme conditions. However, larger units tend to be bulkier and more expensive, so consider your available space and portability needs when selecting a model.
Safety Features
Safety cannot be overlooked, especially in a backup scenario where you may not be present during operation. Features like auto-shutoff if the heater tips over, oxygen depletion sensors, and ventilation requirements help prevent dangerous situations. Ventless models are convenient but demand proper setup to avoid carbon monoxide buildup. Always verify that a heater’s safety features meet local regulations and are appropriate for greenhouse use.
Portability and Size
Portability can be a deciding factor if you need to reposition your heater during power outages or seasonal changes. Smaller, lightweight models like the Mr. Heater Little Buddy excel here but might lack the capacity for larger greenhouses. Conversely, larger units such as the Mr. Heater Big Buddy PRO are less portable but provide more reliable heating over bigger areas. Consider your space constraints and how often you might need to move the heater when making your choice.
Ease of Use and Maintenance
Simplicity in controls and durability are vital for backup heaters, which may be used infrequently but need to perform reliably when called upon. Features like easy ignition, adjustable settings, and straightforward fuel connections reduce hassle during emergencies. Regular maintenance, including checking for leaks and cleaning vents, extends the lifespan and safety of your heater. Choose models with accessible parts and clear instructions for minimal upkeep.
Budget and Long-term Value
While it might be tempting to opt for the lowest-priced heater, investing a bit more in a reliable, safety-equipped model pays off during critical moments. Quality units tend to last longer, operate more safely, and require less maintenance. Consider your greenhouse’s size, climate, and how often you anticipate needing backup heat to determine the appropriate balance between cost and features. Prioritizing value ensures you’re prepared without overspending on unnecessary extras.
Frequently Asked Questions
Can I use a propane heater indoors in my greenhouse safely?
Yes, but safety precautions are necessary. Ventless propane heaters can be used indoors if they have built-in oxygen depletion sensors and auto-shutoff features. Proper ventilation is essential to prevent carbon monoxide buildup, especially in enclosed greenhouses. Always follow the manufacturer’s instructions and check local regulations to ensure safe operation. Regular maintenance and monitoring during use are also recommended to prevent accidents.
How much BTU do I need for my greenhouse backup heater?
The required BTU depends on your greenhouse size, insulation, and climate conditions. As a rough estimate, about 30-60 BTU per square foot is typical for moderate climates, but colder areas may require higher ratings. For backup purposes, choosing a heater with a slightly higher BTU than your calculations suggest provides extra assurance during extreme cold. Measure your space carefully and consider local conditions to select an appropriately rated unit.
Are ventless propane heaters safe for backup use in greenhouses?
Ventless heaters are convenient and easy to set up but come with safety considerations. They produce carbon monoxide, so proper ventilation is critical to prevent dangerous buildup. Many models include safety features like oxygen sensors and auto-shutoff, which enhance safety if used correctly. If you opt for a ventless heater, ensure your greenhouse has adequate air exchange and that you follow all safety guidelines to mitigate risks.
How often should I perform maintenance on my propane heater?
Regular maintenance is key to safe operation and longevity. Check for leaks, clean vents, and inspect hoses and connections at least once a season or before heavy use. During extended periods of inactivity, drain fuel if recommended and store the heater in a dry, protected area. Following the manufacturer’s maintenance schedule ensures the heater remains dependable when you need it most.
Is it better to buy a more powerful heater than I need?
Generally, choosing a heater with a slightly higher capacity than your calculated needs provides a margin of safety for unexpected cold spells. Overpowered units can be less energy-efficient and harder to control, but they ensure reliable backup performance. Conversely, undersized heaters risk failing to keep your greenhouse warm during extreme cold. Balancing capacity with safety features and ease of use makes for the best long-term investment.
Conclusion
For those seeking the best overall backup propane heater, the Mr. Heater Big Buddy PRO offers high heat output and safety features suitable for larger greenhouses. Budget-conscious buyers will appreciate the Mr. Heater Little Buddy for its portability and affordability, while those prioritizing safety and ease of use might prefer ventless models with auto-shutoff. Beginners should focus on simple, reliable units like the Propane Heater Indoor and Outdoor, whereas experienced growers with larger spaces may opt for high-capacity options like the LAANPOLE 15000BTU. Each choice depends on your greenhouse size, safety needs, and budget constraints.
