# Why Does My Sauna Take So Long to Heat Up? The Ultimate Troubleshooting Guide - Canonical: https://33rdsquare.com/why-does-my-sauna-take-so-long-to-heat-up/ - Published: 2023-10-30 - Author: Lillie Gabler - Categories: [Tips](https://33rdsquare.com/category/home/tips/) --- As a home renovation expert who has installed and repaired countless saunas over my career, I know how frustrating it can be when your sauna takes too long to heat up properly. But don‘t worry – with some targeted troubleshooting and maintenance, you can get your sauna heating back up fast again! In this comprehensive guide, I‘ll draw on my 10+ years of hands-on experience to walk you through the top causes of slow sauna heating, and the steps you can take to fix them. Consider me your personal sauna heating coach! First, let‘s quickly review why you want your sauna heating up quickly in the first place. ## The Benefits of a Fast-Heating Sauna It‘s no secret that regular sauna use offers incredible benefits like: - Lowered blood pressure and stress levels - Detoxification through sweating - Increased circulation and heart health - Improved joint pain and muscle recovery - Mental clarity and relaxation But you miss out on these rewards if your sauna takes too long to warm up. The optimal sauna experience involves quickly reaching temperatures between 150-190°F. In my experience, saunas that take longer than 30-45 minutes to reach 150°F often have underlying issues. Let‘s look at the most common causes and fixes. ## Size Matters – Bigger Saunas Need More Oomph One of the biggest factors in sauna heat up time is simple physics – the size of the space that needs to be heated. A larger sauna volume takes longer for the heat to effectively spread, just like it takes longer to heat up a big room vs. a small room in a house. **As a rule of thumb:** - Saunas under 100 cubic feet should heat up within 30 minutes. - Medium saunas of 100-150 cubic feet may take 30-45 minutes. - Oversized luxury saunas over 150 cubic feet can take 45-60 minutes to reach temperature due to their sheer size. I generally recommend keeping your home sauna around 100 cubic feet or less if fast heating is a priority. Let me walk through an example: A sauna that is 4 ft wide x 4 ft deep x 8 ft tall = 128 cubic feet This sauna is on the larger side and will likely take 45-60 minutes to preheat fully once up and running. To improve the heat up time, you could reduce the depth to 3 ft wide x 3 ft deep x 8 ft tall = 72 cubic feet This reduced volume will cut down the heat up time to around 30 minutes – a big improvement! You can use an online [sauna size calculator](https://www.saunas.com/sauna-room-size-calculator/) to estimate your cubic footage. If your sauna takes longer than it used to, de-cluttering can help. Reduce benches, decor items, and wood accessories to improve airflow. I recommend only keeping necessities like a thermometer, water bucket, and towels inside during heating. ## Crank Up the Heat – Your Heater Matters Your sauna won‘t heat up quickly if it lacks the proper heating power – it‘s like trying to heat a house with a single candle. The heating element is the engine that makes your sauna work. An underpowered heater coupled with inadequate heating rocks are a recipe for lacklustre heating. ### Choose the Right Heater Wattage The power of your sauna‘s heating unit is measured in watts. Here‘s what I recommend: - For small saunas under 100 cubic feet, look for a heater with **at least 4500W (4.5kW) output.** - Medium saunas of 100-150 cubic ft perform best with **6000W (6kW).** - Oversized saunas over 150 cubic feet may need **9000W (9kW) or more** for efficient heating. Make sure your heater was properly sized for your sauna‘s cubic footage when installed. Undersized elements can‘t put out enough heat. As a rule of thumb, you need about 10-15 watts per cubic foot in your sauna space. ### Use the Proper Heating Rocks The rocks inside the heater absorb heat, then radiate it into the sauna continuously. Poor quality or cracked rocks won‘t heat effectively. **Use igneous rocks like peridotite or olivine.** Their pyroxene and olivine mineral content retains and radiates heat optimally. River rocks have poor heating properties. Plan to replace your heating stones annually, or any time they become cracked or powdery which traps heat. ### Maximize Your Heating Rocks To supercharge your heating rocks, pour a ladle or two of water over them once the element is hot – the resulting steam helps circulate heat quickly. Be sure to use sauna-grade water, not tap water which can cause mineral buildup. See my guide on [how to use sauna stones properly](https://www.healthline.com/health/how-to-use-sauna-stones) for more tips. ## Lock in the Heat – Insulation Matters Your sauna constantly battles heat loss. Poor insulation = slow heating and difficulty maintaining the desired temperature. Ideally, your sauna walls and ceiling should have an insulation R-value of at least R12. For maximum efficiency, aim for R19 insulation or higher to really lock in heat. Use foil-backed insulation if possible – the reflective layer blocks heat loss by radiating warmth back into the sauna interior. For flooring, always choose insulated sauna-grade material. Uninsulated floors draw heat out of the room. Caulk and seal any minor gaps around door frames or wall joints with high temperature silicone. Look for leaks around vents and ducting as well. If your sauna has windows or glass doors, cover them with insulation wrap which can be purchased online or at hardware stores. For outdoor saunas, definitely insulate the floor even if your walls already have insulation. The ground will leech heat quickly otherwise. ## Ambient Temperature Matters Too If your sauna is in an uninsulated basement or placed outdoors, colder surrounding temperatures will impact heating: - Each 10°F reduction in ambient temp causes 5-10% greater heat loss. - Optimal is to maintain at least 65-70°F around the sauna room. Consider a space heater outside the sauna when in use to offset the cooling impact of lower outdoor or basement temps. Close any uninsulated exterior doors and windows near the sauna when it‘s heating up or in use to prevent drafts. ## Age May Cause Slow Heating Element Performance Like most appliances, sauna heating elements degrade over years of use: - Their ability to reach maximum temperature diminishes. - This causes longer heat up times and difficulty maintaining heat. Inspect your heating elements annually – they should glow red when turned on and have no dark spots. Hire an electrician to test their max temperature output using a thermal camera. Output 15-25% lower than when new means it‘s time to replace. **Plan to replace heating elements every 3-5 years**, or per your manufacturer‘s recommendations. This ensures the fastest possible heating. I install new elements for my clients every 3 years regardless of apparent condition, to avoid premature failures. Replacement heating element costs range $200-500 including labor, well worth the expense to restore fast heating and sauna enjoyment. ## Proper Use and Maintenance Is Key Like any appliance, proper sauna use and regular maintenance keeps it running its best for years. **To keep your sauna heating efficiently, be sure to:** - **Always run the ventilation or leave the door ajar for 5-10 minutes between sessions** – this expels humidity and allows heating elements to cool slightly between high-heat cycles. - **Scrub benches, flooring and walls regularly with disinfectant** to prevent potentially harmful mold and mildew. - **Check for leaks,** which can damage heating elements by allowing moisture inside the heater. - **Inspect any insulation or wall panels for deterioration or damage** which hurts heat retention. - **Ensure vents and ducting are clean of dust buildup** to maximize airflow. - **Test door latches and safety features monthly.** Doors should have functional safety releases in case of an emergency. - **Have an electrician inspect wiring connections and your breaker annually.** Faulty wiring is a fire hazard. - **Replace any incandescent lightbulbs with LED equivalents** to prevent bulb damage from ongoing heat exposure. - **Consider a humidity tray** if your sauna lacks a floor drain – this prevents water puddles. ## Troubleshooting Slow Sauna Heating Step-by-Step If your sauna still isn‘t heating up properly after checking the previous points, don‘t panic. Here is my recommended troubleshooting process: **Step 1 – Double check proper sauna thermostat operation:** - Ensure it‘s set to the desired max sauna temperature. - Test that the thermostat correctly powers the heating element when the temperature is low. - If it‘s functioning erratically, replace the thermostat. **Step 2 – Inspect the electrical supply and wiring:** - Use a multimeter to test voltage at the heating element while on – it should match the rating spec‘d by the manufacturer. - If low, the circuit may have inadequate amperage to power the heater properly. Consult an electrician. **Step 3 – Check for air flow obstructions** - Remove any towels, stools or decorations placed on or blocking vents. - Check that ventilation ducting isn‘t kinked or collapsed. - Ensure intake and outflow vents aren‘t obstructed by anything. Proper airflow is crucial. **Step 4 – Visually inspect the heating elements** - Turn the heater on and look for hot spots or dark colored areas indicating damage. - Check for loose electrical connections to the element. - If the elements don‘t glow red throughout, have an electrician test their output wattage. **Step 5 – Try insulating glass doors or windows** - Temporary cover bare glass with insulation blankets or plastic sheeting to check if it improves heating times. - If it does, consider adding permanently installed insulated glass wraps or coverings to boost heat retention. ## When to Call the Pros While much troubleshooting and maintenance can be DIY, it‘s best to call in a professional for: - Replacing heating elements or troubleshooting complex electrical issues - Rewiring to fix damage or upgrade to meet current safety codes - Major insulation upgrades like replacing underfloor batts - Sealing air leaks in problematic areas - Structural repairs to benches, walls or ceilings - Removal of mold, pests or excess moisture damage - Any smoke, burning smells or strange noises which likely indicate a dangerous malfunction or faulty component. As a general rule, always call in qualified technicians if the issue involves the sauna‘s electrical system, heating element or structural integrity. Trying to DIY complex electrical and heating issues risks shocks, fires or further damage. Hire certified professionals who know how to identify and safely correct problems. It‘s well worth the peace of mind! ## Use Your Sauna Safely It‘s crucial to always use proper safety practices in your sauna: - Stay well-hydrated before and after, and limit sauna sessions to 15-30 minutes max. Listen to your body. - Check with your doctor before using a sauna if pregnant, elderly, or having medical conditions. - Never use a sauna under the influence of alcohol, drugs or medications that cause drowsiness. - Enter slowly and sit for a few minutes before turning on the heat. - Cool down for at least 10-15 minutes after. Avoid icy showers which can shock your system. - Always use a thermometer and don‘t exceed 204°F (95°C) to avoid dangerous overheating. - Understand the signs of heat exhaustion like dizziness – exit the sauna immediately if they occur. - Ensure your sauna has proper safety features like door releases and low voltage lighting. ## Bring The Heat – Get Your Sauna Heating Fast Again Phew – we covered a lot of ground! With a targeted troubleshooting mindset and proper maintenance, you can get your sauna heating back up fast again. As your personal sauna heating coach, I recommend starting with the most common and easiest issues to fix, like: - Reducing excess clutter and size - Replacing old heating rocks - Adding insulation to exposed areas - Testing your heating element output Addressing the low-hanging fruit first often reveals the root cause. Don‘t hesitate to call in electrical professionals when needed – safety first! Here are some additional great resources on optimizing your sauna: - [Sauna Tips and Precautions](https://www.mayoclinic.org/healthy-lifestyle/consumer-health/expert-answers/sauna/faq-20058560), from the Mayo Clinic - [How to Buy a Sauna](https://www.bobvila.com/articles/how-to-buy-a-sauna/#:~:text=Electric%20saunas%20start%20around%20%243%2C000,installation%20bringing%20it%20upwards%20of), a guide from BobVila.com - [Sauna Safety Tips](https://www.health.harvard.edu/staying-healthy/sauna-health-benefits-risks-and-precautions), from Harvard Medical School I hope this comprehensive sauna heating troubleshooting guide serves you well on your journey to total sauna enjoyment. Let me know if you have any other questions – I‘m always happy to help sauna owners! --- Source: [Why Does My Sauna Take So Long to Heat Up? The Ultimate Troubleshooting Guide](https://33rdsquare.com/why-does-my-sauna-take-so-long-to-heat-up/)