10 Best Propane Heaters For Indoor Use 2025 in the United States

The Mr. Heater 18,000 BTU Big Buddy Pro Series Portable Propane Heater is a solid option for those looking to heat indoor and outdoor spaces up to 450 square feet. One of its greatest strengths is its versatility, with a heating range from 4,000 to 18,000 BTUs, making it suitable for various environments—from garages to living areas. Its clean-burning, nearly 100% efficiency is a bonus for users concerned about indoor air quality. Safety features are impressive, including auto shut-off if tipped over, pilot light extinguishes, or low oxygen levels are detected, which adds peace of mind, especially for indoor use. The heater is also portable, which means it can easily be moved to different locations as needed.

However, there are some drawbacks to consider. Although the heater is designed for indoor use, it still requires proper ventilation, which could be a limitation in certain scenarios. Additionally, operating at high altitudes (above 7,000 feet) can cause the heater to shut off, potentially frustrating users in mountainous areas. While the adjustable thermostat control is a useful feature, the recent removal of the fan on some models may affect performance, especially in larger spaces where air circulation is needed.

Another point to note is the requirement for D batteries to operate, which might be an inconvenience for some. Finally, the warning against using unauthorized accessories can be a concern for those looking to customize or extend functionality.

The Mr Heater 4000 to 18000 BTU Portable LP Gas Heater is a versatile option for heating indoor spaces, with a focus on portability and adjustable heating levels. It can produce 4,000, 9,000, or 18,000 BTUs per hour, making it suitable for areas up to 450 square feet, which is great for small rooms or even outdoor settings like porches and picnics. This flexibility allows users to customize warmth based on their needs.

Safety features are a strong point with this heater. It includes an automatic shutoff mechanism that activates if the unit tips over, which is crucial for indoor use. Additionally, it has a low-oxygen safety shutoff feature, ensuring that adequate ventilation is maintained, which is important for preventing dangerous situations with propane heaters.

Portability is another highlight, as it weighs only 15 pounds and is easy to move around. This makes it a good choice for users who need a heater that can be relocated easily between different areas. However, it is essential to note that while it can connect to larger propane tanks for extended use, these accessories are not included, which may lead to extra costs. Users need to ensure proper ventilation when using this heater indoors, as it relies on combustion, and failure to do so may lead to safety concerns. Additionally, the lack of built-in features like a thermostat can be a downside for those looking for more precise temperature control.

The Mr. Heater 30,000 BTU Vent Free Radiant Propane Heater stands out in the indoor heating category, especially for spaces like cold rooms, sunrooms, and cabins. With a robust output of 30,000 BTUs, it efficiently warms areas up to approximately 1,000 sq. ft., making it suitable for larger spaces. Its advanced infrared technology is a highlight, delivering warmth directly to objects and people instead of just heating the air, which can feel more comfortable in chilly conditions.

Safety is a significant consideration, and this heater features an automatic low-oxygen shut-off system. This is crucial for indoor use, as it ensures the heater will turn off if oxygen levels fall too low, providing peace of mind while using it. Additionally, the convenience of a built-in thermostat allows for easy temperature adjustments, and the battery-powered ignition simplifies starting the unit.

There are a few aspects to consider. While it's designed for larger areas, the actual effective heating coverage is about 750 sq. ft., which may limit its effectiveness in very spacious settings. Portability is another point; weighing in at 30.1 pounds, it’s not overly heavy, yet wall mounting is required, which could be a drawback for those looking for flexibility in placement. Being a vent-free model means that it does not require a flue or chimney, which can be advantageous for installation but may also raise concerns regarding indoor air quality over prolonged use. It’s essential to ensure that the room is well-ventilated when using this heater.