Sauna woes Christian Donner, September 8, 2011December 13, 2022 My new Sauna never got over ~150°F – not exactly how it is supposed to be. It took quite a bit of research and hands-on tinkering with the control unit until I got it working correctly. Neither the manufacturer of the hardware nor the vendor of the kit were particularly helpful in this, so I think a summary of what I learned in the process could be useful for a larger audience. Framing and wiring is complete Sauna kits in the US usually come from Canada. After researching options and prices for years, I ordered mine from SaunaFin in Toronto. I opted for a 5×8 clear cedar kit with several upgrades: a cedar door, a double L-bench, a Tylö Deluxe heater with remote control, extra cedar to finish the outside, and little things like headrests, thermometer, bucket / ladle, and of course a timer. Overall, my purchase experience was very positive. The material arrived on time and with minimal damage (despite UPS freight shipping), the price was reasonable, and the cedar was of high quality. Everything fit and nothing was missing. It took about two weekends to build it. Insulation is in I don’t want to get into the details of construction, because the process is sufficiently documented elsewhere, such as in the instructions for the electrical wiring that Saunafin provided. I did, however, have issues with operating the sauna that I want to summarize, because this information is nowhere else on the Web, and because the heater manufacturer, Tylö, who maintains a US representation, did not respond to my requests for customer support. Shall we assume that Tylö is taking preemptive action to protect themselves from law suits? They ship sauna ovens that cannot be operated without altering them, but if something goes wrong, they can always say to the judge: Well, not our fault that the house burned down – they altered the oven! Honi soit qui mal y pense. My problem was 2-fold. First, the heater’s thermal limit switches kept tripping during normal operation. Second, the sauna did not reach my target temperature of about 190°F because the thermostat shut off the heater at 150°F. It turned out that these two things were unrelated, and here is what I did to fix them. Tylö Temperature Limit Switch The Tylö heater has two temperature sensors tucked into the handle on top of the unit. These sensors each trigger a limit switch when they get too hot. Unfortunately, they always got too hot. This is poorly documented. The Tylö manual simply states that frequently tripping limit switches indicate a ventilation problem. In other words, the heat supposedly does not get transported away from the heater fast enough, and hot air backs up around the top of the heater, which leads to overheating. Tylö says that cross-ventilation is always required. There must be a cold air vent below the heater and a hot air vent at the top of a wall diagonally across from the heater. Saunafin simply states in their instructions that cross ventilation is optional, because they undercut the door and that this gap provides enough ventilation to circulate the air in the sauna. I had installed a top vent, and I had the undercut door. The top vent is closed during normal operation, otherwise I would heat the outside. My first intuition was to rearrange the rocks on the heater. I thought that I had packed them too tightly so that they were blocking the flow of air. Removing rocks or rearranging them did note solve the problem, though. Suspecting a flaw in the layout of my sauna, I contacted Saunafin about this issue. As it turns out, this was a known problem, because I received very specific instructions for how to address it – by disabling the temperature sensors on the heater. Sort of. I was not ready for that, figured that Tylö must know better how to install their heaters, and cut a hole into the finished sauna to allow for cross-ventilation. Cold air vent grill I had found this vent grill on Amazonthat was a perfect fit for the job, and in less than an hour I was ready to try out cross-ventilation. It made no difference. The limit switches tripped again. The Tylö manual states that you should call a professional to reset the switches, which is nonsense. The switches are two red buttons on the back of the unit, near the bottom where the electrical connections are. The problem with these switches is that they cannot be reset until the sensors have cooled off quite a bit, at which point I had lost interest in the sauna for the night. The only option left was to accept that the problem was with the heater and not with my sauna. I decided to move the senors a little further down, which was easy enough to do. This radical step took care of the issue, just as Saunafin predicted. Whether it was the right thing to do I still don’t know (Tylö never responded to my request for advice). Lowered temperature sensors for the heater’s limit switch Temperature confusion My other issue – the sauna temperature peaking at 150°F – remained, however. I had installed the sensor for the thermostat at the right height and far enough away from the heater, so that was not the issue. Saunafin suggested that the thermometer may be bad and that the temperature was actually higher than I thought. Funny, since they had sold it to me in the first place. So I went online and found a decent replacement here – even with a Celsius scale. And Saunafin was right again. The new thermometer reported over 80°C when the thermostat shut off at the highest temperature setting. This is equivalent to almost 180°F and is warm enough for me. It still bothers me that I cannot go higher, should I want to. I suspect that there is a potentiometer in the TS30-01 control unit where the temperature limit can be adjusted, and maybe I will open it some day to find it. For now, I am happy with the sauna’s performance and looking forward to many cold winter evenings. The finished sauna Six months later I finally got around to figuring out how to adjust the temperature limit of the TS30 controller. These units use a sensor that consists of a capillary tube and a bulb containing freon. Temperature changes around the bulb result in a change in pressure in the capillary tube, and this pressure change actuates mechanical switches in the dial. There are 4 switches, each with a separate temperature setting. This is how the heater’s stages are operating. When a limit is reached, the switch shuts off power to one of the heating elements. The switches are spring-loaded, and this enbles us to change the limit temperature. Here is my recommended process for raising the temperature limit of the Tylo TS30 controllers beyond 200°F: Set the temperature to max and heat up the sauna until it reaches operating temperature Disconnect the power by switching off the breakers Remove the black plastic frame and the two screws that hold the face plate in place Pull the black knob off the temperature dial Remove the 2 screws that were behind the knob Pull the face plate out and push it down Push the temperature controller in and pull it out from behind, as shown in this picture: Temperature adjustment on the TS30’s thermostat There is strip of duct tape that covers four holes (blue arrow in picture). Pull it off. Now the adjustment screws are accessible (red arrows in picture). Turn them clock-wise in equal amounts to raise the temperature limit. Remember that each stage has its own limit, and by turning the screws in equal amounts, the dynamic characteristics of the system are preserved. Start by turning each screw 1/2 turn. By turning the dial (now without the knob on), you can find out the amount of change that you have made (this is why I recommend that the sauna is heated for this process), because when the limit temperature is reached, you hear an audible click from the switch. Put everything back together and turn the power on Run the heater for 15-20 minutes to see if the new temperature setting is where you want it to be If not, repeat I initially turned the screws too much (several full turns) and the temperature soared past 200°F right away once I turned on the power. This caused the heater’s limit switch to trigger again – a problem that I thought was already solved. I had to repeat the process by now lowering the temperature limit in several steps. I also had to lower the temperature sensors behind the heater further to avoid unwanted shut-offs. Ideally, you want the desired top temperature to be somewhere near the maximum position of the temperature dial. Otherwise, someone could accidentally turn up the heat to a level that might be damaging or dangerous. There is a delicate balance between that and the position of the limit switch sensors behind the heater. It took a few iterations to get this right. Also, because the factory temperature limit settings for each of the stages are optimzed to work together for the most energy-efficient operation of the sauna, there is some risk of ending up with a less ideal temperature characteristic of the system. By turning the screws in equally small amounts, this should be mitigated. Now I get 90°C/200°F – much better and now there is nothing left to wish for. Related Posts:SUTAB Scam?TyreWiz not working after battery changeAmazon threatens customer of 26 yearsEnphase Envoy Local AccessThe Great Cat Litter Poop Off Weekend Warrior saunatylö
Wanted to leave my “thank you” for your post! You are officially responsible for at least 10-15F more in my sauna!!. Found your recommendations at the moment when I realized myself that I have to move temp sensors much lower on the back of the heater to prevent shut off. Also found that they are should not touch metal back of the heater, otherwise shut offs still occur sometimes. Also started to fill evaporator with water at the beginning of warm up to slow down heater’s body overheat. But the main trick of course was your thermostat tweak. II did it the lazy way and just turn the screws 3/4 of a turn. Now I’m getting 185F easy and still yet to try to go for a maximum Thanks again! Leo
You sir deserve a commendation. We built our outdoor cedar barrel sauna kit with Tylo heater in November of last year and have been enjoying it ever since. However, I have never been able to coax the temperature above 145 degrees F. We have always had to boost the humidity in order to get that deep heat in your muscles feeling. We live in the middle of Canada and sauna on any given night including the minus 30 degree nights. Despite this I always felt the heater should be capable of better. Like you I thought that perhaps the rocks were packed too tight and so rearranged them, and like you, found no difference. After finding your Webpage and implementing your suggestions today I just finished my first sauna where the temp topped out at over 175 degrees Fahrenheit and rising. I had to turn the heater off! I would like to thank you very much for taking the time to post your knowledge on the subject and wish you all the best. Howard
Just wanted to add a thank-you to your post. I purchased a home that was built in the early 90’s that had a sauna added about a year after the house was built. At the showings the sauna did not work and the previous owner admitted that they had not used it much. They did however say they would put it in good working order before we closed. Well they got it to start by having a handyman come out a press the little red buttons on the rear of the heater. No one bothered to check to see if the thing would heat for anything longer than about 15 minutes or to 120 degrees F. Because if they had, it would have been discovered that the high temp sensor would trip and then as you experienced, you wait for it to cool and you can start again. After many calls and many trips by the “not-so-expert-handyman” we were nowhere. To add salt to my wound the previous owner now refuses to provide what they promised, a working sauna. To them, the fact that the heater now does turn on, is in their opinion, the end of the story. I called Tylo and they were no help at all. So I began to search the web and look for a sauna heater repair person in my area. A really nice guy at a local pool installer helped me through the way these things work over the phone. He assumed the sensor switch was weak due to the fact that the heater is over 20 years old. But he did tell me about the temp sensors which I could not locate. (they are hidden under the handle) I had him order a new switch and he said he’d call when it was in. After we talked I felt a bit better but continued to poke around on the web and found your blog. I immediately located the high temp sensors (thanks for your picture) and lowered them. The sauna is now working perfectly and the thermometer is regulating the temperature. Your site is the only one that has shown any detail about how to troubleshoot these problems. Thanks again!
Many thanks! Your experience is invaluable, and extremely helpful. Really, is it too much to ask for a hot sauna, after spending thousands on the equipment rendered useless by corporate lawyers? What a shame! Thank goodness for people like yourself, who’ve taken the time and trouble to reseach, experiment, find the solution and spread the word! Free spirit and free speech will always beat the corporate assery!!
I have exactly the same problem now. Today installed Saunacraft heater, and it trips the high limit at 70C. After reading your blog I have adjusted sensor, and now it trips at 90 C (192F). So, thank you very much for sharing your research However, 90 C is still too low for me, because i am looking for 100-110 C. For healthy man this is real sauna temperature (and always been).
I had a similar problem with a Tylo Combi-8. Per US regulations, sauna heaters sold in the US apparently have heat limiters built in that prevent the heating of a sauna above a certain temperature. no idea what that is. I found a quick fix around this problem…cutting out a 1 inch thick piece of cedar and drilling through a hole the equivalent diameter, and length) of the probe (sensor) that protrudes out at the top-front of the combi heater. I additionally soak this wood in water, actually I keep a few similar sized pieced in a bucket of water, and when I turn the unit on I insert the wood over the probe. This is very simply done and I have been able to increase my sauna temp from 175 to over 210 F
This article was posted in 2011 – yet remains the only source of clear and truthful information about sensors location. This is my second Tylo heater. First was bought in 2002 and still works in old house. Back then I found an electrician who did the “magic” and raised the temperature limit from stubborn 70. I moved to the rural area and do not have him around. Local electricians have not heard of the sauna or the heater. They suggested to disassemble the heater to find the thermostat but I was not sure they would know what to do. I did not try to reach to any thermostats – just moved away the sensor and now I have my 100F – or even more if I wanted to. Thank you!
Absolutely the only information available to calibrate a Tylo ts-30 sauna control. My sauna would not go past 150f and finishing the exterior of my sauna saw on hold since I wasn’t sure if I would have to relocate or replace the capillary tube. I knew there had to be a way but I never would have guessed the location of the adjustment screws without the valuable information you posted…thanks. Ps.. in my haste to complete this adjustment procedure, I must have only removed the tape enough to expose three of the 4 screws, thus, left one unadjusted and can’t remember how many turns the others have been changed. Can you recommend a way to “reset” the adjustment and start over using all four screws so I don’t lose the proper characteristics of the thermostat? Thank you .
I don’t know of a way to restore the original setting, unfortunately, other than by replacing the thermostat (which requires replacing the bulb). But I would not worry too much. As long as the sauna reaches your target temperature within a reasonable time (20-25 minutes to 190° in my case) and then maintains the temperature with only one heating element on, you should be ok. But as a last resort you could replace the part.
Thank you very much for a great article and a special thank you for Andrew Grant! I followed his advise and saw my temperature climb to 210F.
Christian: thank you very much. I’m having similar problems. Im embarrassed to ask, but how do you disconnect/ lower the temp sensors? Do you need to remove the heater from the wall? thanks again.
John, I don’t think I removed the heater. I just untangled them and pulled them out from under the handle, then wound the capillary tubes around the springs to get them out of the springs, as you can see on the photo, then wrapped them around each other to keep them centered and away from the back of the heater.
We found the two red reset buttons but they do no seem funtion (can’t push them). How do you use the buttons to reset the heate
Susan, if you don’t hear a load click when you press the buttons down firmly, either the oven is still too hot or they did not trigger and you have a different problem.
Hi there, 5 years later, your post on “sauna woes” is still not only relevant but THE ONLY GAME around for adjusting these units, so many many thanks! I have a question – where did you position the probe on the thermostat? I have a different heater and am replacing the thermostat with the 3-pole version of the thermostat you adjusted (has the same type of adjustments) and I’d like to know where the probe at the other end should be – high, low? In the box, and if so, where? thanks so much, Anna Roma (Brooklyn, NY)
Hi Anna, the Saunafin installation manual says: 59″ above the floor and not directly above the heater. I have it on the opposite side of the door from the heater. It should be in the little plastic holder because the bare metal could burn someone by accident.
why does my sauna only turn on when I turn the timer to the on position. As soon as I turn timer past the on position it shuts off.
Absolutely correct. The handle gets hot. The probes are in the handle. They trip every time. Easy fix, carefully undo springs snd reroute lower between the mounting brackets. Careful, these are gas filled tubes. No bending. Ridiculous design element in otherwise good product. I hope I do not burn the house down. But the sauna is supposed to get hot. Shutting off after 15 minutes does not get it very hot. The handle will boil water, conduction of aluminum part right from the stones. So this a bad place for the limit sensor.
Further observation. The CC10 controller shuts off at one hour. The manual says three. So about 15 minutes after warm up, just when you settling in, it shuts off. I am fine with one hour limit for safety, what if I passed out, etc., but this error in manual confused me. No response from Tylo. Easy to work around, as I go in, after 45 minute warm up, I restart it and get another hour.