A Central Air Heating Element, A PID and a Sauna

[JayPoorJay]

Obviously there is heat loss when you open the door but due to your pressure idea, it all comes out all at once. Forcing air in is a waste of time and energy.

"All"? How much air "pressure" do you think we are talking here? So, the reason for this isn't only the pre-heat, it's also the recovery too, after opening the door... I hear you though...

[JayPoorJay]

You need to be careful about using the wrong type of “thermostat (capillary bulb style) is necessary and controls the on off”
Two reasons one is the contacts of the switch part that can handle the current the other concern is the temperature range of the device plus and the dead zone of the thermostat sensitivity to temperature change these are different do not think that they are the same because they are not

You could probably go with a digital thermostat however you will need to experiment with the temperature on and temperature off and the dead band to keep the system from short cycling which is a detrimental effect on mechanical switch type of contacts

Now you use a sold state relay instead of a mechanical switch type but you still need to have a dead band where you have no ON/OFF state because even if it is digital type of switch you can still overheat the module even if you have a heat sink on it

Now this would require a PID controller to have the best possible result you could possibly do it with out a PID controller but you would have to have the right type of temperature controller that can handle the current rating of the heater unit but if you are using this type you need to know the amount of dead band the temperature controller you plan on using not all of them are the same the best ones are the ones that you can set the ON temperature and you can set the OFF temperature of the heater unit this is the best type to use now some of them have what temperature off set which a predetermined difference between ON and OFF which still can be used but make sure that you have at least 20 degrees difference at a minimum for best results

Now they do make thermostats switches that can adjust the dead band to certain extent but this type of thermostats are more accurate and more expensive to buy that is the reason the thermostat that is recommended is more expensive than a general use thermostat type switch is

Here is something that I found on EBay that you might be interested in a non working heater unit

https://www.ebay.com/itm/40453572545...Bk9SR9SMiOGmYw

Ebay search “electric sauna heater 120 not working”

I plan on one of these... But thanks. I'm just waiting for them to restock...
https://m.vevor.com/sauna-heater-sto...28#goodsDetail

Do you have a specific suggestion for the/a thermostat? That would help. I don't understand them very well. Are they just on off with 120v feed, depending on temperature?

[JayPoorJay]

I plan on one of these... But thanks. I'm just waiting for them to restock...
https://m.vevor.com/sauna-heater-sto...28#goodsDetail

Do you have a specific suggestion for the/a thermostat? That would help. I don't understand them very well. Are they just on off with 120v feed, depending on temperature?

Maybe I just need to spend the $100 dollars and get the one that is original to the temperature/sauna control panel that I have coming? At the same time I cant imagine that a thermostat would react to very small changes in temp regularly to the point that it would cook itself or wear itself out...? More research.

The thing i like most about doing alllllll kinds of DIY projects is the learning curve and all of the things that need to be figured out. The availability of so many devices (amazon) is pretty amazing, I must say. As much, the internet and all of the information that is at the tip of ones fingers...

[diif]

"All"? How much air "pressure" do you think we are talking here? So, the reason for this isn't only the pre-heat, it's also the recovery too, after opening the door... I hear you though...

The fan you are proposing is 160 CFM, it's on from the start of heating up the sauna. There will only be so much pressure the sauna can take before the fan stops working.

[JayPoorJay]

The new and improved wiring diagram,,,
Thanks to the guys at Sauna360...

Pg 9. The 1202-1-18 unit...

Looks like the "contactor" (I was wondering about that) is built into the controller itself (unless I'm mistaken) which is good...

I am a little confused about how and which wires will be run to the individual elements. I think I understand the load connections,,, but am uncertain about the the line back. Anyways, I'm a ways away from that stage.

My elements are 2100watts each 😬

[JayPoorJay]

Is it possible that this entire controller can function on one neutral wire for the heaters AND the light? I just don't understand where the neutral wire back from the elements wires in...or even comes from... headaches...

[sam_sam_sam]

Originally posted by JayPoorJay View Post
Could this be my guy?
https://a.co/d/ab3gAph

Here is the data sheet for the temperature switch

https://parts.rheem.com/product/RPD-47-22861-01

You are not doing your homework for devices that you are thinking about using

https://www.vevor.com/sauna-heater-s...28#goodsDetail

This is part of the description of the device did you miss this part

• Adjust the Temp and Time: The home sauna heater features user-friendly mechanical knobs for temperature and time control, providing you the flexibility to personalize your sauna experience based on your comfort. With a maximum temperature of 230℉ and a timing capability of up to 3 hours, you have full control over your sauna session.

This is not a good match at all not even for a maximum temperature thermo runaway situation you are asking for trouble without even knowing about this is not a good situation to be in

I do not mean to come across rude but you need to read data sheets and understand what the information is telling you about the device that you are considering using do not assume anything when you do a proof of concept getting into bad habits for your first project is not a good way to start trust about this

Me personally I think about doing a modification project that I do not know much about and I have been looking at data sheets and not really finding good matches jet so making progress is going to be very slow at best and at this point I not sure if it is worth going down this rabbit hole and it might be that I can not find all of the information at this point so not being able to completely understand how this device should work might keep me from doing this project

[sam_sam_sam]

Is it possible that this entire controller can function on one neutral wire for the heaters AND the light? I just don't understand where the neutral wire back from the elements wires in...or even comes from... headaches...

See here is another example of the fact that what you do not realize is that this system has 3 120 volt circuits that should not be on the same breaker because of the amp draw that it has

To answer your other question as long as you only use one 120 volt circuit yes you can it is not a good practice to for more than one circuit

But to answer your question the contactor coil is 120 volts or 24 volts depending how what control voltage that decided to use

[JayPoorJay]

Good Morning! Thanks Sam.

So what I discovered is that there is NO neutral to the heating elements. Each element leg (3 of them) gets 120v for a total of of 240 +/- in each of the 3. I was confused and then talked with a electrician at work who cleared things up for me. That N on the board is for the 120v light circuit only, on a separate line, and that is it.

My controller is the 1202-1-18 model/design. See manual.

Thru the controller, three element legs will get its 120v from the T1 connection, 3 will get 120v from the T2 connection.

I will be working with (see page 9 of the manual) the 1 phase layout. L3 and T3 are not used... Power input from the panel into L1 and L2, out to the coils on T1 and T2. It is a residential home and I don't have 3 phase capability.

Now I have to figure out my limiters...and how to place them in the circuit. See page 6 of the manual...

Have a good day

[sam_sam_sam]

Good Morning! Thanks Sam.


My controller is the 1202-1-18 model/design. See manual.

Thru the controller, three element legs will get its 120v from the T1 connection, 3 will get 120v from the T2 connection.

I will be working with (see page 9 of the manual) the 1 phase layout. L3 and T3 are not used... Power input from the panel into L1 and L2, out to the coils on T1 and T2. It is a residential home and I don't have 3 phase capability.

Now I have to figure out my limiters...and how to place them in the circuit. See page 6 of the manual...

Have a good day

Please post a website link to the manual that you are using so we are on the same exact page and we can get the same information together

[JayPoorJay]

I got this from the company. It's an attachment. It was included in post 45...

[sam_sam_sam]

I got this from the company. It's an attachment. It was included in post 45...

One thing I do not like about this manual is that it does not have how you hook up the three heater element are they jumpers plate or are they jumpers wires with eyelet terminals to the wire terminals because you are making the three heater elements in a parallel circuit configuration which 3 heater elements @ 7 amps each for a total of 21 amp current load

One note if your wiring runs are more than 100 feet go to the next wire gauge for best results because you do not want to have a high voltage drop to the system this is my personal opinion and what I go by when doing wiring up a device to a breaker panel

The circuit for light fixture does not need to go to the next wire gauge even if the run is more than 100 feet because your wattage is only 60 watt please make sure that you use a moisture tight light fixture for this space

One thing that is going to be very important thing to do is that you make all your connections to the heater elements are tight and the wires are not over tight enough to strip the thread out of the nuts of the connector board or connector block probably made out of Bakelite material if your connections are not tight enough you will destroy the terminal plate connectors and probably not replaceable so make sure that they are tight enough

Make sure that you use a GFCI type breaker for your sauna system for your safety yes they are more expensive than a conventional breaker but because having steam in this space I would recommend using this type of breaker

I just realized that the way that this system is setup is that one heater element is always on and the other two heater elements are going through the limiter which is interesting concept to do it this way so I am assuming that when the temperature is close to desired temperature it goes down to one heater element it is possible that this device has a two stage thermostat switch this not a common thermostat it is probably a special type of thermostat

The reason I know this is because of diagram number 5 shows how the control system and main system are connected to each other one note the contactor coil is 240 volts which is a little unusual for a control circuit to be using this voltage generally speaking it is 24 volts DC or AC sometimes it can be 120 volts AC

Also pay close attention to page number 14 and follow it very closely for best results how to construct the sauna room
Where you are planning on putting the sauna device that you put the studs in the wall to support it and plan ahead and accordingly so you do not have to redo a section because of poor planning this is not where you want to take shortcuts if you do you will regret it later trust me with this

We might be considering buying one but I not sure that I want to tackle this project myself because one I do not have the time to devote to it to make sure that this project is done correctly and properly this is the reason I have taken an interest in what you are planning on doing your self but when I hire someone or a company to come out to do this project I am going to have them explain exactly how and what they are going to do and if I have any questions or concerns about what and how they are going to do this I will speak up and if they have an issue with this then they are not the company that I will use

Now if I can find this in a kit form I might consider doing it myself but it will depend on how much more money it would to have it professional done versus getting it kit form and weather or not it worth the the extra money or not

[JayPoorJay]

Great information! Thank you Sam.

Wire runs will not be more than 4ft.
Most likely, less than...

There will be NO steam or water near this set up. But there will be GFCI breakers/terminals used. If possible

If you would, from this ED,,, can you please provide an example of a limiter switch that can control the system, switching from 3 to 1 element(s)? I don't know what that is...

I appreciate your help (and warnings) with all this.

[sam_sam_sam]

Great information! Thank you Sam.
If you would, from this ED,,, can you please provide an example of a limiter switch that can control the system, switching from 3 to 1 element(s)? I don't know what that is...

I appreciate your help (and warnings) with all this.

Unfortunately the manual does not say anything about it so I am not sure exactly what type of device it is maybe someone on this forum might have an idea about what type of device this is

[JayPoorJay]

Good Morning All...

Just to say, I got this thing working and working well. I built the fire brick chimney, got a nice fab'd shroud to direct air flow, a nice 36 inch grill/grate for inside the sauna and a surprisingly nice vevor fan to push air thru... And it works. Max temps I see coming out of the vent (without ceramic insulation on the ducting) is about 250F with fan running in medium... I'll be come forward with some pictures shortly.

Q: I want/need the fan to run WHENEVER the system is on. I have the relay you see and the wiring diagram (I'll attach a picture) and I am having trouble figuring out how to wire the coil side of the relay to trigger it when the power comes on. Can I just put the coil side in one of T1 or T2 circuits. That way when the elements are getting power, the relay will be triggered?

Help please.