Circuit board burned

[SorryImaNewb123]

I have a hot tub with Gecko S Class circuit board. When I went to heat up the tub earlier, started smelling burning smell and started seeing smoke. I shut off power immediately!

A few hours later I opened the circuit board box and found that one of the cables from heater burned as well as where that cable screwed into the circuit board.

A week ago I noticed 3 dots steadily blinking on the control screen, so now I am remembering that YouTube says it may be a flow condition or HL condition. I should have ignored it.

Can someone please advise what likely happened here???

 

[ajw22]

Let's see what @RDspaguy says.

 

[RDspaguy]

Most likely it's just a burnt terminal or relay. It may have been caused by a heater short if it's not on a functional gfci, but probably just age.
The three dots could indicate another issue or could be because your heater isn't working now from the board damage and the system knows it. I would troubleshoot them as separate issues.

 

[SorryImaNewb123]

what’s strange is the 3 dots and subsequent burn issue happened after I used a different brominating concentrate then usual. I have always used Bioguard, but I tried Clorox brand and that’s around the time this all happened.

 

[Jimrahbe]

123,

I really, really doubt that this has anything to do with your brominating levels or brands..

Thanks,

Jim R.

 

[SorryImaNewb123]

123,

I really, really doubt that this has anything to do with your brominating levels or brands..

Thanks,

Jim R.

Ok, just a coincidence. But thought worth mentioning. Thx for letting me know.

 

[RDspaguy]

dots and subsequent burn issu

Wrong assumptions lead to wrong solutions. Are you certain the dots were before the burn?

used a different brominating concentrate

High oxidizer and/or low ph damage heaters. Damaged heaters can damage boards/relays, but rarely if on a gfci as required by code.
Stuck relays can overheat and damage heaters and sensors (the likely cause of the dots).
Loose/worn/corroded terminal connections (at the board or heater) can get hot and damage the board and/or heater, as well as sensor wires if too close.
But regardless of cause, from the pics I'd say you'll want relays on the board (local electronics shop) and a new heater/sensors.
You can test the sensors and heater with a multimeter, if you'd like me to explain how.

 

[SorryImaNewb123]

Wrong assumptions lead to wrong solutions. Are you certain the dots were before the burn?


High oxidizer and/or low ph damage heaters. Damaged heaters can damage boards/relays, but rarely if on a gfci as required by code.
Stuck relays can overheat and damage heaters and sensors (the likely cause of the dots).
Loose/worn/corroded terminal connections (at the board or heater) can get hot and damage the board and/or heater, as well as sensor wires if too close.
But regardless of cause, from the pics I'd say you'll want relays on the board (local electronics shop) and a new heater/sensors.
You can test the sensors and heater with a multimeter, if you'd like me to explain how.

I don’t know if the 3 dots showed up there just before the burn. I just noticed them previously and turning off/on the power to spa made those dots go away. But I believe turning the heater up did cause them to come back in the past.

Here’s some addition pics after I removed the board from the case. Shows the damage front and back, heater (which looks in perfect condition), the cable that goes from heater to board (note it only burnt on the board side, the other half that connected to heater was unharmed.)




Thanks for your help so far. I really appreciate it!

 

[RDspaguy]

You can't always tell a heater is bad from looking, but that does look like a bad connection at the board or perhaps crimp-on terminal. The local electronics shop should be able to do the work, though they may have trouble finding the relays. The relay may still be functional, but you can see it got hot. I'd replace it.