Jump to content

Issues with a L.A. Spas gecko board.


d.sebens

Recommended Posts

I acquired a "free" hot tub.  A 2003 LA Spas hot tub.  It has a gecko s class in it.  They guy offlined it 2 years ago because it was overheating to the point it would trip the mechanical high limit switch.  When I got it it would not heat at all.  I removed the board and found the heater thermostat relay and high limit relay solder had been melted and dried out.  I reflowed the solder and it worked fine for about 18 hours when I came back to it you could smell burnt.  I removed the board and found that it had burned through the board and damaged the high current strip that joins the high limit relay and the thermostat relay.  

I didn't have the means to repair the board at that point so I sent it off.  A guy epoxied the board back to fill it and replace both relays and the high current strip.  When I installed it I saw an instant arc flash.  It looks like it came from beneath the relay.  I took it out and looked at it, it had burned the high current strip a little(burnt from the top side down to the bottom). I patched it with an extra wire soldered on to the strip and retested.

 

If I connected everything except the heater, no sparks.  Connect the heater and it sparks.  (In an effort for clarity, this is a low flow model AND the tub has no water in it.  I only turned the breaker on for less than a second, like flipping a light switch on).  With no heater you can see the low flow led's blinking.


The thing is is that I measured resistance of the heater, 10.3 Ohms hot to hot and OL to ground on both.  Maybe I am doing it wrong but 220 divided by 10 makes 22 amps, 220 * 22 makes 4840 watts.  The heater is set up for 5.5Kw.  So what gives?B7208FC3-BEF6-4A06-A23C-AE05C945A07C.heic  Also at first turn on should it be powering the heater without the flow switch pressed?830E7158-6415-472A-929A-5501FFA47CE4.heic896EE5E7-C5EF-498A-BCA1-890E3DBFDC3A.heic

Link to comment
Share on other sites

Your attachments are not available.

10 ohms at 240v is 5760 watts, rounded off for 5.5kw. 

The heater can run in an empty spa for a minute if everything is working, depending on the control system. It can run much longer with part failures. This can be a stuck relay, bad board, bad flow/pressure switch, etc.

It would help if we could see a pic of the circuit board and wiring diagram on the box cover so we know what you have there.

Link to comment
Share on other sites

The pictures aren't great to show what I found but if you look at the first and last picture.  Pictures 1 & 3 are pre electronics guy repair and 2 &4 are post repair.  I am missing the C5 capacitor.  I am not sure what it is for, I emailed the guy but I ordered  some more based off the other caps.  This one looks like it goes from the heater high current pad to resistor just down from it.  I don't think it is any sort of dampening or clamping for the coils inductive field because it is on the high current side and not all relays have a corresponding capacitor.  

 

I am patching the board back up and will replace this cap.  I removed the high limit relay and it looks good.  I see no reason it should of arced like it did other than it seems like it is coming from by the capacitor mounting.  Hopefully this is the issue, either that or it is some sort of current monitoring circuit.

Link to comment
Share on other sites

Well I tend to be impatient and post before really looking stuff over.  I ordered a new cap to replace the missing one but I dont think that circuit is utilized.  On other circuits there is a cap and resistor and they go to stuff.  On this one it goes Heater terminal pad>Cap>Resistor and then the trace just ends.  Even shining a light through it doesnt show any circuits hidden.  I'm not sure what purpose this served.

Link to comment
Share on other sites

Ok. It doesn't look like the relay was replaced to me. Just the burns "repaired", if you can call it that. As for the rest, I have no clue what you mean. I do not do electronics repair and would have replaced the board or control system entirely.

You seem to know some electrical, then you don't. You talk of repairing circuit boards but have not even tested the relays to see if one is stuck and why. That system should not fire the heater without water pressure, so your pressure switch is bad or your relay is stuck.

  • Like 1
Link to comment
Share on other sites

No the guy repaired the board.  I am okay with soldering and have nothing to lose so I have been messing with it.  Both of those relays are new.  I forgot to mention when I first got it I bench tested the t-stat relay and it would click but had no continuity so I unsoldered the p3 relay since I don't have a blower and used it on that one.  I'm sorry I should of spaced out my pictures.  That is a mix of before the guys repair and after.  The guy is saying it was a loose heater connection caused it to arc yet there is no blackening on the heater terminal.  Then he said it must be a dead short despite I gave him resistance readings of the heater.  Then I find out he didn't reinstall the capacitor after the repair which after looking at it seems like it isn't utilized anyway but thats besides the point.  He has since stopped responding to me it seems.  He at least gave me my money back even though I hadn't asked for it.

Link to comment
Share on other sites

I will check  the flow switch with my multimeter when I attempt repair 7000. I will leave the heater unhooked and monitor voltage on the heater terminals.  My current theory is it is trying to jump from the high limit relay straight to the heater. When I removed the relayi noticed that it was missing conformal coating on the edge of the heater pad where it’s been burnt. 
 

I figure I have nothing to lose attempting to fix this board. Breaking it worse still ends up with it broken and needing replacement. 

Link to comment
Share on other sites

3 hours ago, d.sebens said:

I figure I have nothing to lose attempting to fix this board

Nothing at all. This guy tried to DIY his circuit board and fried his spa a couple of years ago not far from me. Insurance asked me to go out for a look. Look at the siding. 

You sound like you know what you are doing.. he did not. Know your limit and stay within it as they say.

 hot tub fire cambridge

fire cambridge hot tub

  • Like 2
Link to comment
Share on other sites

Looking online at replacement packs, the s class with the metal box like mine says it is rated for a 4000w heater. Did someone wire mine too hot? Should I wire it down less?  It has a chart of how to wire it for different wattages. 
 

My board number is 9911-500117 rev f. 
 

the problem is that I can’t find any specs for the board. 

Link to comment
Share on other sites

I would leave it. The chances the previous owner rewired it are slim to none. You could change the jumper setting to LC or low current...but you likely won't be happy as it will cut the heater off when you run the pumps in high speed but it might work for you. Turn off power to change the jumper. 

See the schematic for the jumper settings and location on the board

Where are you located? (country)

Link to comment
Share on other sites

While waiting for a part to come in I was researching different boards. What’s the difference between these boards? 
 

Plastic s class pack

Metal s class pack

The metal one is a lot more.  My topside is tsc-44  and only the metal one says it will work  is it a different board or do they just not acknowledge that control anymore?  
If I end up needing a new board what do you think my best route would be?  It’s got the low flow heater so I don’t need one with a heater/circ pump and from what I can tell it was jjm connectors currently wired.  Also in the listing the metal one says JJ connectors and the plastic one says JJM is that different, the pictures of them like the same.

 

Link to comment
Share on other sites

Welp, I am throwing in the towel.  I am tired of trying to repair this.  I am fairly sure it is arcing from the high limit relay to the heater connection.  I am going to hook the heater up to power with an inductive amp clamp on it and check amperage on it to see where that is at.  But either way I need a new board.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Unfortunately, your content contains terms that we do not allow. Please edit your content to remove the highlighted words below.
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...