When considering the heating options for a log burner hot tub, the debate often centers around whether to opt for an internal or external stove. Each type presents its own set of advantages and disadvantages, affecting everything from heating efficiency to the amount of space available for bathers.
In this post, we’ll delve into the key differences between internal and external hot tub stoves, including aspects such as heating time, cost, space requirements, efficiency, maintenance, and safety considerations for.
Key takeaways
- Internal stoves heat the water more quickly due to their direct contact but take up valuable space inside the tub, limiting the number of users.
- External stoves, while heating more slowly, enhance safety and ease of maintenance, and do not reduce the capacity for bathers inside the tub.
Why Still Use Wood Heaters in 2024?
Wood heaters remain a popular choice for many due to their cost-effectiveness, efficiency, and sustainability. Wood heating can be a viable and economical option, particularly in regions where wood is plentiful and inexpensive. Wood heaters provide a consistent and robust heat source, making them ideal for maintaining comfortable temperatures during cold weather.
They are also a renewable energy source, reducing dependence on fossil fuels and minimizing carbon footprints. Additionally, advancements in wood heater technology have significantly improved their efficiency and safety, making them a reliable choice for modern heating needs. Read more about the facts and figures of wood heating on this article from Penn State Extension.
Internal and External Hot Tub Heater Comparison
Internal stoves, typically more budget-friendly and quick to heat, immerse directly in the water, taking up more space but offering efficient heat transfer. On the flip side, external stoves, while requiring more setup space and longer to heat, are user-friendly, easier to clean, and eliminate burn risks for children by being positioned outside the tub.
Whether you prioritize cost, space, efficiency, or safety, understanding these differences can guide you to the best choice for your wood-fired hot tub needs.
| Internal Hot Tub Heater | External Hot Tub Heater | |
| Efficiency | Faster heating due to direct contact with water | Can heat large volumes efficiently with the right power |
| Heating Time | Generally heats water faster | Takes longer to heat water |
| Energy Efficiency | Highly efficient with minimal heat loss | Less efficient due to heat loss to the atmosphere |
| Operational Costs | Typically lower | Can be higher due to longer heating times |
| Space Considerations | Reduces available space for bathers | Requires additional space outside the tub |
| Safety | Requires careful handling to avoid burns | Reduces burn risk as heating element is away from bathers |
| Maintenance | Harder to maintain | Easier to clean and maintain due to accessibility |
| Suitability for Families | May not be ideal due to space and safety concerns | Better for households with young children due to reduced burn risk |
1. Heating Time and Efficiency
The efficiency of heating water in a hot tub is a critical factor for many users. Internal stoves offer faster heating due to their direct contact with the water, but external stoves, with the right power, can also heat large volumes of water efficiently. The choice between the two often comes down to balancing heating time with energy efficiency and operational costs.
2. Space Considerations
If space is a premium, internal stoves might not be the best choice, despite their efficiency. They reduce the amount of available space for bathers, which could be a significant downside for those who frequently host friends or family. On the other hand, external stoves require additional space outside the tub but leave the interior completely open for users.
3. Safety and Maintenance
Safety is paramount, especially in households with young children. External stoves significantly reduce the risk of burn injuries, as the heating element is located away from the bathers. They are also easier to clean and maintain, given their accessibility. Internal stoves, while efficient, require careful handling to avoid accidents and can be more challenging to maintain over time.
Why Choose Internal Hot Tub Stoves?
Internal stoves are placed directly inside the hot tub, making them a compact option if you’re looking to maximize the heat transfer from the firebox to the water. This direct contact means the water can heat up relatively quickly, typically within 2 to 4 hours, depending on the stove’s power and the volume of water.
However, they take up significant space inside the hot tub, which could limit the number of people who can enjoy the tub at once. While they boast high efficiency due to 100% of the heat transferring directly into the water, internal stoves are less convenient to clean and pose a higher risk of burns, as the heating element is accessible to bathers.
This design brings several advantages and some drawbacks:
1. Efficiency
Internal stoves are known for their high efficiency because they transfer nearly all the generated heat directly into the water. This direct contact means that the heating process is maximized, reducing energy loss. Consequently, these stoves can heat the water more quickly compared to external stoves.
2. Cost and Availability
Generally, internal stoves are less expensive than external ones, depending on the model. The simplicity of their design and installation process often translates to lower upfront costs.
However, the options for internal heaters are more limited, with fewer brands manufacturing these models. They are primarily chosen for specific types of hot tubs, especially those where space and aesthetic integration are less of a concern.
Internal heaters are less commonly found in retail outlets and may require special ordering or direct purchases from manufacturers.
3. Heating Time
Due to their placement within the water, internal stoves heat the water faster. Typically, they can bring the water to a comfortable temperature within 2-4 hours, depending on the stove’s power and the volume of water.
4. Space Considerations
One significant drawback of internal stoves is that they occupy space inside the hot tub. This can reduce the number of people the tub can accommodate. For example, a hot tub designed for six people might only comfortably fit four when an internal stove is installed.
5. Safety
Internal stoves tend to be safer in terms of burn risk because they are submerged in water and often fenced off from bathers with a dedicated separation fence. This design minimizes the risk of accidental burns, making it a safer option for families with children.
Installation Idea: Recessed Installations
One significant advantage of internal hot tub stoves is their suitability for recessed installations. If you plan to install your tub into a deck or floor, an internal heater is a better option. External heaters require access from underneath the floor, which can be inconvenient.
Internal stoves, placed directly inside the tub, allow for easy access and maintenance without the need to reach under the floor. This makes them a practical and convenient choice for installations that are recessed, ensuring a seamless and hassle-free experience.
What are External Hot Tub Stoves?
External stoves sit outside the hot tub, connected via heat-resistant hoses that circulate water through the heater to warm it up. This setup is easier to clean and safer, particularly for families with children, as the hot surfaces are kept out of reach.
Though external stoves require more time to heat the water, typically over 4 hours, they don’t intrude on the bathing space, allowing for more occupants in the tub. The primary drawback is that some of the heat escapes to the atmosphere, making them less efficient than internal models. However, they compensate with greater ease of use and maintenance, alongside enhanced safety features.