Callaway Cedar Tub Control Unit Went Poof! Photos now attached

[cedar tub]

I have a Callaway cedar tub. I've had it since Oct, 2008. It developed a leak around one of the jets and has sat idle since Jan, 2011. I finally found the same jet they were using and replaced that one last month. I filled the tub yesterday to let it run a day and sanitize and then I was going to drain and refill. I had the temp set to 70.

Here is the sequence of events:
1. The fill water when it went in was still a little over 70 and the tub ran through it's purge cycle and the the normal two hour filter cycle and stopped.
2. I went out around 11pm to check on it and the temperature readout on the controller said 71.  So I know everything was still working at 11pm.  I knew it would probably activate the heater sometime in the middle of the night once the temp dropped another degree or two to 69/70.
3. This morning, I went out to check on it and the display was dark.
4. I checked the main breaker box outside and it was tripped. I reset it and the tub went through it's normal startup and purge sequence which is 30sec. After that, it switches to it's 2hr filter cycle. It normally takes about another 30sec before the thermostat activates the heater which is what happened.  I was right in front of the heater and the main electrical panel for the tub.  I heard the thermostat click and saw a blue flash and then a tiny bit of smoke and the electrical smell all at once (in the vicinity of the main tub electronics panel and the heater). The breaker tripped at the same time. I removed the cover from the the tub's electrical panel, but I don't see any problem.  I suspect something has shorted in the electrical panel.  Would a bad heater cause this to happen?  

*This tub has it's main electronics panel, pumps and filter on an aluminum skid that can be placed away from the tub.  That skid and the main electric breaker are right next to each other.  The actual tub control panel is attached to the main electronics panel and can be remote mounted.

[cedar tub]

After I typed this, I went back out and reset the breaker.  I removed the cover from the main electronics panel and watched the sequence again.  The same thing happened, but this time I know the problem is inside the main electronics panel.  

This is the outside of the panel.  I forgot to mention there is also an ionizer.  This whole thing is normally covered to keep the elements out.


I think the red and black wire are the ones that connect to the heater (?).  Directly behind what I think are relays is where the electrical flash occurs.  Again, it happens when the thermostat trips the heater.


I also notice the presence of some rust on the connectors from those wires


The heater is directly behind this panel:


What if I were to remove the two wires above and try it.  Would that tell me anything?

[Dr. Spa™ Ret.]

The spark/flash may be normal. If you remove the wires you'll disconnect the heater and this will tell you if the heater is bad (if it then doesn't trip).

[cedar tub]

Well, I removed the two nuts and wires and set the heat to 75 so it would come on.  The tub ran through the purge and has now been running for about 5-min.  So, the heater is bad?

[cedar tub]

After doing a little more research, I believe this is a self inflicted problem.  As I said in my first post, I have just replaced a jet.  I filled the tub to check the jet and to let it run with some sanitizer.  I did not balance the water and only added some chlorine.  I was going to drain, refill and then balance after I ran it a day.  I think the unbalanced water could have damaged the heat coil.  Am I on the right track here?

[cedar tub]

After doing a little more research, I believe this is a self inflicted problem.  As I said in my first post, I have just replaced a jet.  I filled the tub to check the jet and to let it run with some sanitizer.  I did not balance the water and only added some chlorine.  I was going to drain, refill and then balance after I ran it a day.  I think the unbalanced water could have damaged the heat element.  Am I on the right track here?

[Dr. Spa™ Ret.]

The unbalanced water may have damaged the heater...if it's been unbalanced for months or years.  a day? no.

[cedar tub]

The unbalanced water may have damaged the heater...if it's been unbalanced for months or years.  a day? no.

It has sat unused since January and there was probably some bad water in the heater tube.  I'm draining it today and will try to figure out how to open the heater tube to look at the element.

[Dr. Spa™ Ret.]

The element will "look" just fine. If disconnecting the heater stopped the GFCI from tripping, 99.9999% of the time, the element is bad and needs to be replaced.

If you're going to go to the trouble of taking it apart to "look", you might as well replace the element as that's almost certainly the problem.

[cedar tub]

The only thing preventing me from getting the whole tube off the back of the electric panel is the round thing with the yellow label.  It goes through a small hole and into the heater tube. 

[Dr. Spa™ Ret.]

That's the pressure switch...and it simply unscrews from the "whole tube".

[cedar tub]

OK, I got it disassembled and managed to get the element out of the tube.  Getting it out of the tube was the hardest part of all.  I found center mount Titanium versions for around $49.  The one I removed didn't look bad at all, so I hope this fixes it.  After I disconnected the wires, the tub ran for over an hour before I shut it off. 

[cedar tub]

I received my new element this week.  I have probably already ruined it trying to get it into the tube.  I will know soon.  In the mean time, there is a wire and I can't remember it's purpose or where it goes.  I think it is related to the pressure valve.  Can anyone ID this wire and what it's purpose is and where it should be connected?  I remember removing a nut or a screw and it just fell out.  I don't know if I broke it or if it is supposed to look like this.

[Chas]

I would guess that wire is for converting from 220 to 110volt or the reverse, and it is most likely not used. It looks like it is heavily insulated with shrink tube, so I'm guessing it was that way already.

Now, if you can see metal a the very end, then is it possible that some sort of connector broke off. Then you will have to go through a wiring diagram and see where it goes.

If there are any instructions on converting voltage on labels or stickers, I would start there.

HTH

 

[cedar tub]

Chas, I think you are correct.  I think that is nothing more than a sealed end.  However, it was exiting the back of the metal box that houses all the electronics.  I'm going to see what happens.  I may try to check with rh hot tubs.  The bought a lot of the inventory left over when Callaway went out of business.

I do have another question about the element.  It touches the inside of the stainless tube.  Is that a problem?  It seems like it could be.