6 Essential Maintenance Tips for Traditional Sauna Heaters

Wood Burning Sauna Stove

You’re in the sauna after a long work week. As the steam rises, it lifts all your concerns away. Completely relaxed, you lean back on the bench.

Your steam therapy session is going just as you had imagined it. Until…the heater turns itself off before the set time. You can’t think of what could be the cause of this interruption to your me-time.

To avoid such unpleasant scenarios, it’s important to carry out proper maintenance of your sauna heater. This helps you stay on top of any developing problems and eliminates inconveniences to your unwinding sessions.

Today we’re exploring what it takes to keep the centerpiece of your sauna going strong. As we do so, you’ll discover:

  • The impact of cleaning on sauna longevity
  • How to care for sauna stones
  • Different maintenance tips for electrical heaters and wood-burning stoves
  • When it’s best to consult a repair technician for sauna maintenance

Let's look at some simple safety measures you can take to ensure your sauna heater continues to serve you well for many years.

1 - Inspect the Heater

Harvia Vega 3500 Compact Electric Sauna Heater

Imagine what would happen if you used your car day after day without taking it for professional service or even checking it yourself for any issues.

One day you’ll be on the way to an important meeting then your vehicle gives up in the middle of the freeway where it’s difficult to get help.

If only you had taken the time to do regular inspections, you would avoid the danger, embarrassment, and inconvenience of being stuck on the highway. The same also applies to the maintenance of sauna heaters.

Expert Tip: Regularly checking your heater helps you to catch any issues early and helps to prevent them from escalating into major problems both for the heater and yourself.

For example, if your electrical heater develops rust on the internal elements and you allow it to spread, this can damage its structure and reduce its effectiveness in warming your sauna room.

A wood-burning stove with cracks, on the other hand, can allow smoke to escape into the steam room, posing health risks when you breathe in the fumes.

Also, a faulty heater increases the likelihood of accidents while using the sauna, making inspection all the more important.

Periodically check the wiring components of your electric heater to ensure everything is in good working order. If you notice any loose connections either tighten the wires or call in a professional to fix the issue.

Equally important is to test the accuracy of the time and temperature control systems. Electric heaters allow you to set a limit on the maximum temperature and minutes that they run before shutting off to ensure your safety.

Harvia’s Vega 3500, TopClass, and Kip Electric Heaters, for instance, feature a 60-minute timer, preventing the risk of extending your sessions.

To check whether these systems are still working well, dial in the values you want and let the heater run while you're outside the sauna. Take note of when the heater shuts off and confirm if it's accurate.

Do this with different time and temperature settings so that you’re sure there are no errors at any point. After you check the control systems, remember to reset them before using the heater again.

If you have a wood-burning stove, look over its entire structure thoroughly. Ensure you check all the components:

  • Chimney
  • Fire chamber
  • Vents
  • Flue collars
  • Heater legs/stand
  • Door handle

Remove the sauna stones and scan the heater with a torch to see if you can spot any holes in the fire chamber. While small cracks can be fixed in some instances, the safest move is to replace your stove with a new one.

If the chimney is blocked with debris, consult a professional for help with cleaning it out. This saves you the time and energy of taking apart the pipe and ending up with soot all over your hands and sauna room.

For gaps in the chimney seal, reseal the joints with heat-resistant cement. However, if the pipe itself is damaged, you need to have the affected section replaced.

With each purchase of heaters from Sun Valley Saunas, you receive an installation and operation manual. This handy document contains instructions for wiring, operating, troubleshooting, and maintaining your heater.

Using this manual as a checklist when inspecting the heater is a great way to ensure you don’t leave out any part of the device.

We recommend doing inspection checks at least once a month, whether you use an electric heater or a wood-burning stove in your sauna. This will help you spot any developing problems in good time and give you peace of mind that your heater is in good condition.

2 - Clean the Heater Properly

Picture yourself at the end of your steam therapy session, feeling like you’re floating on the clouds. Your mind and body are relaxed, and your worries all melted away. Only to notice a gritty feeling on your skin.

Where could the grime have come from?

Most likely, some components in your sauna have accumulated dirt buildup, one of them being the heater.

Keeping your heater clean helps to ensure a clean sauna experience for you and your family, as well as extend the heater’s life while maintaining optimal heat distribution.

Before cleaning your heater, ensure it’s completely turned off and cool to the touch to avoid burning your skin. For an electric heater, use a soft brush or vacuum attachment to carefully remove dust, cobwebs, or debris from the interior.

If you're using a wood-burning stove such as the Harvia M3, remove the ash and any wood remaining from the previous session with a broom and dustpan.

The exterior of your heater also needs some TLC. Over time, moisture streaks and limescale may form on the outer frame. While these don't affect the performance of the heater, they take away its visual appeal which waters down your unwinding experience.

To clean your heater, it’s safe to use one of the following options:

  • A water and vinegar solution
  • Citric acid powder
  • Mild soapy water

Wiping the surface gently with these cleaning agents and a soft cloth does the trick. Within minutes, your heater will be looking good as new.

3 - Take Care of the Stones

Harvia Sauna Heater Stones AC3000 (5-10cm) (45 lbs)

You might be wondering what kind of care sauna stones need since they don’t have any technical components.

As you enjoy your sessions, the rocks accumulate oil and sweat on the surface. This turns into a layer which affects heat distribution throughout your steam room.

Also, because of their exposure to temperature and humidity changes, the structural strength of these stones changes over time, leading to cracks and eventual crumbling.

As such, it’s essential to inspect them regularly to ensure they’re in great condition.

Once a year, clean the rocks using warm water and a soft brush to eliminate dust and debris.

Pro Tip: For safety reasons, wait until they are cool before doing so. Work on each one individually instead of all of them in a pile so that no stone is left unturned.

After all the rocks are clean and dry, reseat them in your heater.

They should be loosely surrounding the heating elements, allowing enough room for air flow. Placing the stones too closely together restricts air movement, causing your sauna to take much longer to heat up.

If your heater is electric, such as the Harvia Vega 3500, carefully restack the stones so as to not damage the heating elements. Lay larger stones closest to the heating elements to support them and prevent bending or move freely.

Learn how to arrange sauna stones in the video below:

Ideally, you should place smaller stones on the top wherever water can be sprinkled.

Harvia’s Cilindro models, pillar heaters, and electric heaters with large stone capacity, for instance, feature a wide surface area for throwing steam.

In wood-burning heaters, the same principle applies. Arrange larger stones at the bottom of the heater and smaller stones towards the top. This ensures that larger stones closer to the fire box retain heat better and keep the room warm for longer.

Smaller stones at the top create better steam, since water is poured onto a larger surface area with more free space in between the rocks.

If your sauna heater shuts itself off after repacking the stones, it’s probably not getting enough air. Try resetting the rocks more loosely, covering the tops of the elements with only one layer.

Apart from cleaning the rocks, you need to replace them when they start falling apart. We recommend doing this after 300 hours of use, which is approximately one year.

The grit produced by crumbling rocks can damage the stainless steel of your heater elements, leading to costly repairs or replacements.

Note: Remember to only use rocks from the supplied heater brand. Otherwise, you could void any warranty on your heater in case the stones damage it. If you’re unsure where to buy new sauna rocks, we’ll be happy to offer guidance.

Brand-specific sauna rocks are customized for use in steam rooms, and crushed to the appropriate size thus allowing for the best airflow around the heating elements.

4 - Ensure Proper Ventilation

Harvia M3 SL Wood Burning Sauna Stove

In saunas, adequate ventilation is key for preventing the buildup of excess moisture within the room. This not only protects the walls and benches but the heater as well.

Excess moisture causes rust to form on the frame and internal elements, which could damage the entire heater if left unchecked.

Leaving the sauna doors and windows open when not in use helps to air it out and prevent it from remaining damp.

Using a towel to wipe surfaces after your sessions also goes a long way in keeping the sauna room dry.

Don’t forget to clean the exhaust fan located at the outflow vent. A fan that’s weighed down with dirt is inefficient at drawing out humidity from the sauna, pausing the risk of damage to the heater.

"Works great. Cranks my 6x6 sauna up to 190 with ease!" - Kevin Deckard

As for the heater itself, ensure you clear any dirt from the air inlets in the case of a wood-burning stove. This creates a clear path for air to reach the burning wood and provides you with a soothing experience as the sauna room warms up.

5 - Seek Professional Help

Sometimes, the issues you’ll find when inspecting your sauna heater could be way beyond your level of being able to handle them. In such instances, it's best to consult a professional technician.

They have the expertise to fix such issues safely and quickly, saving you the hassle of spending much time doing guesswork during the heater troubleshooting process or getting the repairs wrong.

Examples of serious problems with sauna heaters include:

  • Worn out electrical wires
  • Damaged heater elements
  • Blown out circuit breakers or fuses
  • Large cracks in wood burning stoves
  • Malfunctioning electrical control units
  • Overheating or underheating with no obvious cause

Remember to deal with a technician whose specialty is sauna heater maintenance and repair. This way, you'll be able to rest easy knowing that your heater is in good hands. After all, sauna heaters don’t come cheap.

At Sun Valley Saunas, our traditional heaters come with a two-year guarantee. This gives you peace of mind knowing that if your heater develops any problems within this time, you're covered.

Also, we love to help our customers not only at the time of purchase but also afterward. If you have any concerns about your sauna heater, we’ll be happy to guide you on what steps to take to ensure everything is running smoothly.

6 - Use the Sauna Regularly

Harvia M3 Wood Burning Sauna Stove

All work and no play is no fun! One of the easiest ways to help your heater stay free of problems is to use your sauna often.

By using the sauna at least two times a week, you prevent excess moisture from accumulating, which keeps mildew at bay. High humidity and the presence of mildew reduce your heater's efficiency and lifespan.

Under these conditions, an insulating barrier forms around components of the heater, thus obstructing heat distribution and causing uneven temperature levels in the sauna room.

Also, a buildup of moisture and mildew growth can affect the heater's safety features, such as overheating protection systems and electrical grounding. This poses heat injury and electric shock risks to sauna users.

Our Recommendation: Keep your steaming sessions between 30 and 40 minutes. This allows enough time for air to circulate within the room, eliminating any stagnant air and excess moisture from previous use.

So, take every opportunity you get to indulge in a therapeutic steaming session. Your body, mind, and heater will be all the better for it.

Keep Your Sauna Heaters in the Best Condition With Proper Maintenance

Sauna heaters are robust pieces of equipment, but they need proper upkeep for them to work at their best. A well-maintained heater will provide you with many happy years of enjoying the goodness of steam therapy.

The best part is, caring for your heater doesn't require you to do the most. With a few simple measures, your heater will remain in good shape and take pride of place in your sauna.

Quickly troubleshoot common issues with your traditional sauna heaters using this comprehensive table, outlining potential causes and maintenance solutions.

Symptom Possible Causes Maintenance Solutions
Insufficient Heat Worn-out heating elements Replace faulty elements
Uneven Heating Blocked vents, damaged parts Clean vents, repair or replace components
Excessive Smoke Dirty or clogged chimney Clean chimney, ensure proper ventilation
Electrical Issues Faulty wiring, loose connections Address wiring problems
Inaccurate Temperature Faulty thermostat Calibrate or replace thermostat
Rust and Corrosion Moisture exposure, lack of maintenance Sand, treat, and repaint affected areas

If you have any questions about issues with your sauna heater, please reach out to us today. A friendly team is always at hand to help and will be delighted to walk you through how to ensure your heater stays in the best working condition.

"I found this company to be very professional with prompt service, high-quality products, and they guarantee them. I highly recommend Sun Valley Saunas." - Cynthia White

Wes McMahon

Wes McMahon, is the founder of Sun Valley Saunas and a seasoned ski town sauna enthusiast. In early 2021, Wes transitioned from being an attorney and sauna aficionado in Sun Valley, Idaho, to founding Sun Valley Saunas. His deep appreciation for the Finnish sauna tradition has helped him understand and select high-quality, hand-built saunas for customers throughout North America. Combined with his understanding of the therapeutic and communal benefits of sauna culture, he advocates for the wellness practices that saunas can bring to your overall health. Got questions? Get in touch by calling 1-855-963-5665 or

Important: The information provided in our articles about saunas and related topics is intended for general informational and educational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult your healthcare practitioner before using saunas, especially if you have pre-existing health conditions or are pregnant. Individual health needs vary, and what benefits one person may not be suitable for another.


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