My Amerec 240V / 8 kW sauna heater with analog controls appears to have given up the ghost, on one of the coldest times of the year, when I use it the most. I’m having an electrician look at it soon. It is very likely an issue with the contactor box, as it doesn’t turn on at all, even though the contact makes noise. If I’m lucky, it is just dust or loose wires in the contactor box, and an easy fix.
If the contactor box needs to be replaced, though, it would be another story. But per heater specs, it is a model with built-in contactor box. Amerec has a kit to retrofit the new contactor box into the old heater. They also sell a new touch screen control called SaunaLogic 2 that is Wifi-enabled. There is not much information about the SL2, but one vendor states that it is “available from any location with cell or data service”, which very likely means it’s cloud dependent, and I have no desire to pay top $ for a feature that might be taken away when their cloud servers shut down.
Even if I can repair the old system for now, I have been thinking about adding smart features to the sauna heater for a while. The heater takes a long time to heat, about 30 minutes. It makes a lot of sense to add the ability to pre-heat it from another location - typically, if I’m outside in the hot tub, and decide I want to use the sauna afterwards, but don’t want to get out in cold outdoor temperature, and walk back inside to turn it on manually, then go back into the hot tub while waiting for the sauna to heat.
I’m wondering if anyone offers a sauna heater system that has smart remote control, and can be used without a cloud dependency in Home assistant. I would very much like something that is UL or ETL listed, for insurance purposes. So far, I have not found anything. Has anyone else been there before ?
People have used both ESPHome and shelly to replace control. But that is not going to be UL listed.
If your UL listed choice you found is cloud based, you might consider using that device but limit either cloud access or power to the unit to times of use.
So, electrician just gave me the bad news. Heater won’t start even when forcing manual contact, bypassing the contactor box. Thus, the entire sauna heater needs to be replaced, as well as its controls.
Sauna heater is quite spartan device. 3 heating elements , relays, thermostat, timer and fuse. If your electrician can’t locate the problem, call another.
Thanks. I will make further inquiries. But labor is extremely expensive in my area. I live in a very isolated place, and trip charges are high. Even if another electrician finds the issue, I would likely have to order parts, and have him come back for a subsequent visit to install them, and the repaired system would still lack smart controls afterwards.
I have had this sauna heater for 15 years, but it is actually 27 years old. It makes some sense to me to consider replacing it with something that has smart controls, if a local UL solution exists.
Find below the main components but I would recommend you work with a qualified electrician if you are not familiar with this (never bypass the original temp sensor).
Obviously, this could vary based on your sauna hardware and location. I have a very simple set up with mechanical controls (North american split phases)
These are normally replaced when the body is so rusted that it collapses
Anyway, what ever approach you take, if you need help here, at least post the exact model.
I’m not aware of your local UL though…
One of the key reasons for the no-cloud requirement is to prevent enshitification. I have had several IOT devices suffer various regressions from forced updates performed over Internet. The issues include bugs such as connectivity problems, loss of local access, forcing the use of a cloud server and account when none was previously required, and reduced functionality.
For inexpensive plug-in devices, it is at least possible to replace them easily without the labor costs. For a permanent installation like a sauna, however, I really want to be able to control the firmware, and make sure it doesn’t automatically update and enshitify. That means not connecting the device to the Internet, to prevent the forced updates. Or connecting it only temporarily when there is a known-good security-only update.
Unfortunately, most IOT devices don’t allow manually rolling back firmware, so blocking the updates in the first place is the main way to stop the regressions.
I just don’t want to invest in a smart system that is cloud-only, and will very likely lose its remote functionality over time, something that’s especially likely to be the case over a decade from now.
Thanks. I see that the contactor says it “complies with UL bulletin 508”, but not UL listed. Not sure what an insurance company would make of it.
What kind of enclosure are you using for the dev board ? And where would you locate it ?
Also, what about the physical control panel ? I still want to be able to be able to turn on the sauna from the wall control, not only through Home assistant. For simple on/off functionality, I could use a scene controller. But it also needs to be possible to set the temperature at the wall, as well as session duration. I’m not sure what kind of control would work best. I prefer tactile buttons rather than touch screens. A display might not do very well unless it’s specifically designed for high humidity bathroom, as my current control panel is not far from my shower area.
The control panel is outside, also in a NEMA box. https://www.amazon.ca/dp/B005T6S9H6
All original controls are functional.
However, I generally use the Home assistant dashboard on my wall mounted tablets to preheat the sauna, control the timer, check temperature, etc. Especially in the winter months…
The dev board is located just under the control panel, in its own enclosure (not shown, picture taken prior to final installation)
It also contains a second ESP32 for WLED lighting:
You could use Shelly Plus 1-UL to drive the original contactor.
Whatever approach you choose, make sure the off-timer is handled inside the controller, so once turned on, the timed off doesn’t require any connections to cloud or HA.
Thanks. That looks like a really nice installation, but it’s very different from mine, and I’m not sure how I could retrofit something like this. I wouldn’t even know where to start.
There isn’t anywhere near the amount of space available that you have. The Amerec controller pictured earlier is on one side of a drywall, and the heater is on the other side of that wall, inside the wooden sauna enclosure, near the floor. There can’t be more than 12 inches of thickness between the two, quite possibly less.
The power comes to the heater comes through a conduit run from the main electrical panel to the house, which is behind another sauna wall, on the outside.
What I would like to do is keep an outside physical control. The existing analog one would be fine. I don’t plan on installing any tablet. This just drives up the cost, and I’m not fond of touch screen and unnecessary displays. I would turn on the sauna either locally from an analog wall control, as I have been doing, or remotely from my phone on local Wifi. How could one design something that works this way ?
I believe it makes more sense to replace my heater than try to repair it. The labor to diagnose & fix is likely going to cost far more due to labor costs & repeated trip charges, not to mention parts delay, whereas replacing the heater should be trivial and very quick with all the existing conduit in place.
I started researching other sauna heater units. It seems that many of them feature built-in controls, which would not be suitable for my use case. What kind of heater unit are you using ? I would need to keep the same 8 kW heater size due to the size of the breaker, which is 50 amps.
