First let me say I have no idea as to the manufacturer of the spa. I inherited it from the previous owner.

It worked fine for a good while, maintained a temp of 104. Cover is brand new and works great.

Last weekend I added some water because the level was low. No leak but just didn't fill it high enough the first time. I did not change the thermostat setting (it's an old dial with tick marks). I came out the next day and the heater was on, and the temp on the termometer was 110 !. I'm not sure why the heater was on; it should have gone off at 104.

So then the heater wouldn't click on at all. I looked for the high limit switch but could not find out how to reset it, so I figured it was probably internal and when the temp cooled down it would reset itself.

Sure enough, when the temp dropped the heater was able to click on. Great I thought...back to normal.

Well, I went out last night (week later) to find the heater on, with the same setting as what should be 104...and now the thermometer reads 94. I'm getting flow, but I don't know where to go from here...

Thanks for the advice. I'm handy with a multimeter and know how to work with (and respect) electricity, so I'm confident I can solve the problem...just don't know where to start.

Hi mchad21, Your thermostat may have failed, but we need more information on the unit (pictures etc. ) before we can point you in the right direction. " title="Smile" />

ok thanks for the quick reply !! I'll get some photos in the morning. What exactly would I need to take a photo of? And what exactly comprises the thermostat? I see the thermocouple/sensor in the water, but not sure what exactly has 'failed'.

THe unit's faceplate says 'TDI Command Center'. It's a dial type thermostat with no digital readout, if that helps.

Thanks again !

Hi mchad21, Controller, and controls (spaside), Brand name of equipment, and or spa, wiring configuration 110v- 220v and year if possible. " title="Smile" /> These guys are pretty good, and sometimes just the brand and year of controls will suffice. " title="Wink" />

The year I have no idea, the spa side controls I can get the faceplate info tomorrow.

It's 120V.

When you say wiring configuration, what info are you looking for?

I did a little surfing and it looks like I can remove the controller faceplate and replace the thermostat..?

I'm sure it will be very easy once I understand it better. Tomorrow I"ll be able to see it in the light of day and get a better handle on how things are connected.

Looking forward to it !!

So you don't suspect the heating element? Why or why not?

Also, I have noticed that the thermostat did not hold a tight temperature; i.e. I would have to turn the dial quite a bit to get the heater to click on or off. I don't know if thermostats fail completely or degrade over time, but if it's the latter I definately had been noticing that the temp control was not what is used to be.

Hi mchad21, The TDI Command center is a generic ( and good ) Spa side controller. http://spapartsnet.com/Reference-Catalo... 3_0_1.html Tri Delta Industries has been producing spa side controllers (thermostats) for a long time. If your TDI has a grey cable going to a plastic bulb (thermistor) in a dry well (Plastic tube " title="Smile" /> ), then it is a solid state controller. I don't see a lot of those overheating a spa, so the problem may lie elsewhere. :" title="Question" /> The box that the TDI plugs into is what we need info on. It should say somewhere on it the manufacturer. Let us know when ya have a chance " title="Smile" />

Thanks. Mine sort of looks like that..I"m sure I have an older model. I know that there is some info on the 'box' that the controller plugs into. I"ll get it first thing tomorrow.

What other culprits may have caused this problem? I don't know exactly how the system works, but if the thermostat was bad, wouldn't it not call for heat, or call for heat constantly? The latter happened and the temp went up to 110, and the heater did not shut off. But now the heater is on continuously, and from what I can see, there is no heat. So if the thermostat was bad, you should either have a) no heater activiation, or b) heater on all the time.

If the latter occurs, then the temp should now be at 110.

Maybe it's not the problem?

Hi mchad21, A typical overheat is the result of a runaway thermostat. Mechanical Thermostats with microswitches, and toungston (sp) points tend to have a propensity to stick with age. As the switch paddle moves from the "Ready"points to the "Heat" points, arcing and pitting of the contacts occour. all it takes is one episode of a physicly stuck set of points, and we are too hot to get into. This is where the "high limit switch" comes to save the day. It's design is the same as the t-stat, however it's callibration is 122-126 degrees in the heater chamber. A solid state controller doesn't suffer the same wear, and usually fails differently. Another remote possibility is a mild short from the element on line 2 to casing ground, completing a circuit of a piloted leg, causing a glowing of the element. ( What?) That's why I want to know of the box. Either way it's broke " title="Crying or Very sad" />

wow, looks like I'm going to learn a lot from you..!

I see how it could fail and overheat, but why then would it not overheat again? Apparently it's calling for heat, and has been for a while continuously, but the temp is not even close to what it was before (110degrees).

Something I just can wrap my brain around.

Hi mchad21, I'll bet your high limit switch did trip. High limits are required by UL, and without them, you would have a unique work of modern art in your backyard. " title="Wink" /> As the switch tripped, it killed one phase of your heater, and now the system is desperately running, and running to heat in accordance to the t-stat. Some manufacturers tie in the high limit to the pumps, and heater, and others to the entire system via a "Systems Contatctor". If yours just kills the heater, then the rest of the system is oblivious to the problem. I have seen ( or felt ) high limit reset buttons located in a position requiring a mastering of "Twister" to reset. " title="Laughing" /> ( Keep in mind I havent seen this unit, and may be way off base) " title="Wink" />

ok, starting to get it. I could not find the limit switch to reset; I originally thought the reason the heater would not go back on (after I turned it down from 110) was because the limit switch tripped. I looked around and couldn't find it, so I assumed it was internal.

Then when the thermostat did kick on again, I figured everything was fine. Apparently it was not, and maybe that switch needs to be found and reset.

The original problem was the sticky thermostat, which needs to be replaced. But the heater will not heat back up to where the switch is 'stuck' at 110, beacause the limit switch needs to be reset...??

Still don't understand why the heater came on in the first place if the limit switch was not reset...?

Hi mchad21, There is the possibility that the high limit is self resetting. I am used to a bi-metal plate with a "Push to reset" button. If a physical sticking of the points occour, then you can smack the spa side, and jar loose the points. If the high limit trips, then the amperage across the points dies, and the points may seperate. If this happens after the switch trips, then you have the scenario as now. Otherwise, the element may have failed, etc. You said the spa is 95 degrees. It may be that it is not heating at all, and the 95 degrees is residual temperature supported by the equipment byproduct heat. ( Geesh it sounds like I'm Grasping for it now EH?) " title="Laughing" />

yeah, I don't think it is heating at all. That was my assumption. The temp now is just what is left over from when it hit 110.

I will post picks of the internal box tomorrow. Thanks for all the great info and have a great night !

Hopefully we can figure it out tomorrow.

ok here are the pics. Pic 1 is of the controller faceplate

Pic 2 is of the thermostat wire going into the filter area. The other end of the wire goes into the controller.

The other pic is of the 'box' that the controller is connected to. The mfg. is 'CRL' with a serial number of 0399. I can provide more pics or info if needed.

I see a piece of PVC, with couplings on both sides. Looks to be about 12 inches long and probably 1 1/2 inch diameter. Could this be the heater element? The funny thing is, is that no where can I see any connections into the PVC; i.e. flow switch, limit switch, etc. There is nothing. I'm assuming they are all internal to the CRL 'box', because if it wasn't there would be no way for the thermostat to communicate with the pump/heater, I would think.

Other info: The unit's GFI and the GFI receptacle it's plugged into did not trip, and have never tripped. I cannot see any high limit switch to reset. Maybe it exists, maybe it's an internal mechanism and resets itself?

Hopefully this helps a little bit. I can dismantle whatever parts are required. It's tough to take photos though because there is a gazebo built around the tub, and the access door is on the short side. THanks again all !

here are a couple more pics. One of the pump, and one of what I think is the heater manifold. There are no penetrations thru the manifold, no compression fittings to house switches, etc. The wire attached to the top of the pipe is just used to hold the light in place...it does not penetrate the PVC.

Usually the heater is housed in a stainless steel tube. I have had 2 hot tubs where they used a PVC tube. I would trace the wires from the control box to the heater. The flow switch almost always is on or near the element as well.

thanks. Is it possible the element and switch are inside the CRL box (what is the proper term for that thing anyway)?

I don't see any switches, compression fittings or stainless steel...nothing except PVC. The only individual wire I see is the thermostat wire.

I guess the next step is to remove the cover of the 'box' and see what it looks like. I'll take another photo as well.

Those additional photos must have been posted while I was typing my reply, as I did not see them. That wire going to the "PVC" is actually a ground wire attached to a steel tube. This is a current conductor. You might have two of these in the tub, with the heater element located in between. This is an old school way of doing the heat setup in the tub. Now days you have the stainless steel tube. You won't find one here. You will likely have a "Tee" fitting attached to a length of PVC in which the heater element is attached. Look for this. Usually they are 2" in diameter. It will have what looks like an electric water heater element in it, if I'm not mistaken. There may be a metallic or plastic box attached to the end of that "tee" fitting as well.

ok some more photos. I see the 'Tee', and the wire going across it, but it does really go to anywhere. The other picture you can see it is bonded to another pvc pipe, but from there it is just used to hold the light in place.

The other end of the wire, on the right side of the 'Tee' doesn't go anywhere either.

Is this the conductor you are referring to?

that black box (image labeled 129-2952_IMG.JPG) is your heater housing. The box attached at the left side is where your power connections are. You have the type of element that has a square flange attached to the box with 4 bolts. That copper wire is in no way support for anyting, it's your ground for your current conductors. All metallic objects connected to the tub need to be bonded together, and that is what this is for.

I apologize, I forgot about that style of heater, even though I've had 3 of em LOL

ok we are moving in the right direction !!

Thanks for the heads up on the ground wire as well. I'll have to make sure everything is connected.

Now, on the the fun part..

What is my next step to diagnosing this problem? And where would I find the limit/flow switches to check them?

limit and flow switch should be also in that box... flow switch for sure. It will be screwed right into that square flange of the element if I'm not mistaken. First thing I would do is when you turn on the heat, I would check for voltage at the two large terminals of the element (in that box on the left side). If you have power there, great, now we have to disconnect those same two wires from the element and check the element for resistance across those two terminals. (of course remove power before doing this) The reading should be around 11 ohms. If it is open (infinite) then the element is bad. If you don't have power there, or is less than your line voltage, then we need to do some more checking. Check to see if there are any red buttons (about a 1/4" in diameter) in there. Press it and see if it clicks. This would be the high limit switch. Checking the pressure/flow switch, I would turn on the system, ensure water is flowing, and literally short the two wires going to the switch together, and recheck for power as above. The only thing the pressure switch does is makes sure that water is flowing to turn on the heater.

Hi mchad21, Did you find the high limit yet? :" title="Question" />

ok I did some checking and here is was I found:

Line voltage at the receptacle was 121 V.

Voltage at the terminals of the element, when the heater was on, was, I'm pretty sure, zero.

I say 'pretty sure' because the leads on my fluke sometimes crap out, and you have to get it just perfect to get a reading. The area is VERY tight, but I did the terminal and the wires coming off if it with a neon tester and..nothing. I'm going to borrow a Wiggie from my brother tomorrow and verify for sure.

I did not measure resistance, and I did not see any button anywhere in the enclosure.

Hi mchad21,
Check under the heater box (where you were metering) It may be a metalic red button.

ok it COULDN'T have been that easy..

Found the red button. Pushed it in. It's more of a post not a button, but it is red.

The one thing I did notice is that when I pushed it in, and turned the heater back on, a red light on the control panel illuminated. Not sure what it is because it isn't labeled, but it wasn't lit up before (when the heater, or whatever, wasn't working).

And the terminal from the element is now energized...

Man oh man I think we found it !!

Hi mchad21, Well it's kinda like we were saying last night. Your mechanical thermostat stuck, and overheated the spa. The high limit did it's job, and killed the heater. Then it ran, and ran without power to the element. Push the reset, and back in business. NOW you can expect it to run maybe a week or less before acting up again untill you replace your spaside controller. " title="Smile" />

well, the temp right now is right around 90F. I will heat it to the same seting (roughtly) as I normally do to achieve 104F. If the thermostat doesn't kick off we get to 110F again, then the thermostat is the culprit.

Replace it and that's it. If it doesn't act up, well, it could have been my fault in that I set the dial TOO high. It doesn't take much and there is no digital display, only tick marks on the faceplate. It was dark...I was tired...heck I don't know.

Right (jeez I sure hope so)?

Hi mchad21, Exactly. If a spaside will maintain a preset temp in accordance with it's dial position, then it is a viable work around from replacement. Technicly, if I see a spa side controller allow ANY thing over 106 degrees ( 104 + or - 2 Degrees) Then I must deem it faulty. The Industry Standard maximum temperature for a consumer portable spa is 104 degrees F. Keep an eye on it, and enjoy " title="Smile" />

I sure will. It seems like an easy fix to replace the thermostat, if need be.

I want to thank ALL of you for all your help. I learned a lot about something that was foreign to me.

Thanks again and I'll keep you all posted if I have any other issues.

alright, one more quick question concerning the thermostat....

Assuming it is ok and doesn't stick again, it still has an issue with not being about to control very well. For me to get the heater to energize, I need to turn the dial, in my opinion, way to far. And to get it to shut off...same issue. This isn't a matter of a few tick marks...it's a lot more than that.

I'm not sure if this is a limitation of a non-digital system, or if the thermostat is getting worn out. If I do replace it, would it fix this problem to the point of better temp control?

If so, I will probably just replace it..it would be worth it.

Thanks again !

Hi mchad21, The spaside you have now is mechanical. The new ones are solid state, and maintain temperature better. http://spapartsnet.com/Control-Panels/A... 4_0_1.html ( with all due respect to Spa Babes, Do NOT atempt to Re-callibrate your t-stat. It would be much like putting a dress on a pig) You will need the adapter plate if you order one. P.S. You have a Gerico Spa with a Hayward pump, and Brett Aqualine "Spa Builders" pack.

wow...a full blown ID !! You guys are amazing.

Ok the solid state is a possiblity. If I just wanted a replacement for my current thermostat, can you point me in that direction as well?

Thanks !!

BTW how did you know all that from just a few pics?

Hi mchad21, The link provided in the last post is the site for parts here. I actually am not affiliated with this organization, and it would be rude to point you elsewhere. The Spaside controller is one piece, and you cannot just replace the hermeticly sealed thermostat. A Hayward pump is unique in it's apperance, and apparantly Gerico certainly approved of it enough to slap their label on it. The plastic heater was used long ago by Brett Aqualine industries, and even though it is a "CRL" Knockoff, it is still a Brett heater. (Kinda like a Jeep is a Chrysler) With all the different manufacturers mixed up in the soup, we ( my guys) try to relate products, and componants to gain an immediate image of the spa. ( an annoying habit to some " title="Laughing" /> )

oh I see. Then what is the purpose of buying just a thermostat, like I have seen on other sites?

So my option if the thermostat goes bad is to replace the entire controller?

Not a big deal, just trying to find out my options.

IMO I would just replace the thermostat only IF that is the problem. Sure, the latest and greatest would be nice to have, but there is genius in the simplicity of the older designs. The parts are cheap, redily available, and usually have a good long lifespan.

That was my idea. If I could just replace the thermostat, and not the whole controller, that would be the cheaper way. But if that is not possible, and the whole controller needs to be replaced, then so be it.

But only if the problem persists. I'm still curious...can I just buy a new thermostat, and not the whole controller, if need be?

BTW I checked the spa this morning. The heater was not on, which means that the thermostat did it's job. The temp is right at 104-105degrees. Just to make sure, I kicked the heater on and checked the indicator light. It was illuminated.

Either this was a one-time problem, or it will be an ongoing battle.

The Genious in the simplicity of older designs involves the expansion of liquid from a capilary bulb, up a copper tube, into a pressplate, altering the angle of a rocker plate, which then depresses a micro switch, moving a single pole double throw paddle from the ready light terminal to the heater on points. The portable spa thermostat (Invensys, Eaton Meyers, Sun ) were born of the boiler industry. It makes no sence to me to break open a 15 year old Aquaset, and install technology designed to run an apartment complex boiler. What will really bite is if after you sweat over the spaside controller, a month later one of the air transmitter bellows pukes. The industry has gone away from mechanicle thermostats, and now the thermistor makes more sence. I personaly hate High Limit service calls for the very reason this post is 4 pages long. If the controller were solid state as I posted from the begining, then overheat would be trouble shot differently. I have also seen the modern work of art in the back yard before. I am not a "Pack Changer", but will not subject my consumers to repeat problems resulting in call backs for myself. ( Ouch............. I just fell off of my soap box....) " title="Smile" />

I completely understand, but....

I'm really interested in knowing what I should do next if this thing craps out (being fiscally responsible, of course).

Hi mchad21, You will need a replacement spa side controller. http://spapartsnet.com/Control-Panels/A... 4_0_1.html A spaside, or remote spaside, or aquaset, or thermostat, in your case are all one in the same. When I keep refering to your thermostat sticking, it is your "Command Center" unit I am refering to. It has a probe to read the temperature, and a large J&J style Aquaset plug. They are very easy to replace. The new TDI spasides are smaller (Fit old 2 button style) which is why you will need an adapter plate for the larger hole in the shell. The equipment may be nearing it's end of trouble free run, and another drastic non-fiscal option would be a retrofit of the equipment.

ok, now it is clear to me, thanks.

So for my unit I could get the 2 button mode, since my unit is not equipped with a blower. That button is useless at the moment. Or would I need the three button model because I have three buttons now?

When you say adapter plate, what are you referring to?

Hi mchad21, Correct, The controllers come in 2, 3, & 4 button configurations. If you have an extra button, then thats all it is. Tridelta Industries manufactured two different styles of controllers. The Two Button, and the larger Three, and Four Button. When Technark bought them, they decided to only manufacture the 2 button size, and offer an adapter plate to accomodate the larger series 3, and 4 button. http://spapartsnet.com/Reference-Catalo... 3_0_1.html

ok, so I could just go with the two button version (light and jets) and I should be ok with the plate? Or do I need the plate regardless because I have three buttons now?

Thanks again for all the help.

plate regardless

well, all was fine for a couple weeks, but went out tonight to check and it was back it's old tricks.

Up around 109 at the 104 setpoint. And wouldn't turn off until I turned the dial all the way down and left it there for a few minutes.

It's now not reseting at the limit switch, but this is exactly what happened last time. If I come back in about 30 minutes I'm sure it will reset.

I'll be purchasing the new thermostat and adapter plate now..

Thanks everyone for all their help on this. If I run into trouble with the new install I'll hollar...but it looks pretty easy.

Thanks again.

so now I go out a day later, and hit the high limit switch. It depresses, which last night it would not do because maybe the temp was too high...?

Anyway, the heater will not click on. So maybe the unit is completely dead? Last time around, the heater clicked on after about an hour or so.

Thoughts?

nevermind, I checked it this morning and it clicked on.

Quick update

I just received the new controller, digital model. It has 5 round pins at the male connection; the female connection in my spa as 5 round pins plus 1 'hot' electrical prong.

Is this a problem? I haven't installed it yet and have a call into the vendor as well.

Thanks.