Electrical arching

[Pmtwigg]

So I just replaced the control panel on my Windsor 3 hot tub. When I flipped on the power there was electrical arching at the spot circled on the photo. It appears to be the heating element. I'm wondering what I did wrong. I did not touch any wiring in my work. I simply unplugged the control panel and put a new one in. Please help

[CanadianSpaTech]

When you say control panel do you mean the topside control panel or the main (circuit board) control panel. 

There are obvious signs of corrosion around the heater element. For the cost of a heater element I would replace. You will have 3 options General service. Teflon coated and Titanium.

I would go Titanium. Google 5.5 KW offset heater element. Example here: https://hottubwarehouse.com/products/hot-tub-heater-element-25-4034-bi

Not a hard job to replace. Just make sure the element is not touching the sides of the tube when installed. Check for this when you remove the tube it may be whats causing the arcing.

Does the spa have a "Salt System"? I see blue green corrosion on the copper tabs.

There is a nut under (3/8" or 1/4") the copper tabs that you have to hold when removing the 3/8" nut on top of the copper tab. If you do not hold the nut underneath when loosening or tightening you will break the cold weld and it will be junk

Remove the copper tabs so they are not touching anything and try resetting the power. Test the tabs for 240V using a multi meter to see if you have clean power off the circuit board and this will tell you if perhaps you have a stuck heater relay on the circuit board.

Safety first when testing live 240 if you are not 100% sure don't do it

[Pmtwigg]

 

Yes. I was replacing the upper control panel. The buttons weren't working. 

This does not have a salt system. It is just quite old. 

I removed the terminals and they looked nasty underneath. I dont have a multimeter. The free one I got from harbor freight is broken. 

When I test am I using AC or DC?

 

 

On 9/2/2020 at 6:10 PM, Pmtwigg said:

heating element

 

[CanadianSpaTech]

Should have 240V AC touching one lead to each copper tab. Heat indicator light should be on. If you can turn temp down far enough so the heat indicator goes off and test again you shouls get 0. This will tell you if you have a stuck relay or not...but looking at the corrosion I would say replace the heater element and clean up the tube and copper tabs with a light sand/scuff pad before reinstalling. 

[Pmtwigg]

Should I just buy a relay too when I buy the heater? Hopefully relays arent too expensive. When I disconnected the heater, everything else on the tub was working correctly. 

Also, thank you for helping me.

[CanadianSpaTech]

You would have to take the board to an electrical repair professional to have the relays replaced. They are not expensive but require some talent to re and re along with the proper tools. Again replace the heater element $40 for the part and address any other issues after that if any arise. 

[Pmtwigg]

According to my multimeter, I am getting 0 VAC at the terminals. I dont know how that is possible because there was electrical arcing there before I disconnected the heater. 

[CanadianSpaTech]

Pull the board and look on the back for burnt /darkened areas around the relays. You sure the spa was calling for heat and the heat indicator light was on when you tested for 240vac. Likely a blown heater relay. Replace them all.

[Pmtwigg]

The light on the control panel nor the circuit board is indicating that the heater is being sent power. Could it be that there needs to be continuity? The heater isn't hooked up. Sorry I'm a mech engineer, not an electrical. 

[Pmtwigg]

No burnt fuses. They all have continuity 

[CanadianSpaTech]

2 hours ago, Pmtwigg said:

Could it be that there needs to be continuity

No the 2 copper tabs should be giving you 240 when you touch both copper tabs with your multi meter. Red on one tab black on the other. If you are calling for heat on the topside and you are getting 0 VAC from the copper tabs then you have an issue on the board and is likely a relay is stuck, burnt out or pitted and no longer making good contact.  

You can test the heater element for continuity but not always a true test. If you test it and there is no continuity then yeah it's bad element but you can test it and have continuity but still have a bad element.

You have a rusted element and needs to be replaced if it has not yet failed it will in short order.

Please post photo of the inside cover with the diagram and also one of the new topside.

When you ordered the new topside did you order the exact part number off the old one?

Looking at the overall condition of the board in the pic I see a lot of rust on the screws holding the board in place, Around the heater element, on the union that attaches the plumbing, the green on the copper tabs...it would usually indicate that the board got wet at some point. The relays on that board are open style and with all the indicators there is a good chance to contactor tabs inside the relays are also rusted/pitted/corroded and are no longer making good contact. 

From this side of the interweb I would say you need to replace the relays on the board and also a new heater element. My electronics guy does all the relays on the board for around $150 CDN parts and labour. Heater element $40 so for under $200 you have a "new" board and element good for years to come. JMO

[Pmtwigg]

I turned the unit on for longer and it did show the heating LED on the top panel. At first it was flickering quickly, then it went solid. Then I did read 240 volts at the heater terminals. The heater did have continuity. I have ordered a new heater, I sincerely hope that is all I need

 

[CanadianSpaTech]

Replace heater element and good to go. 

[Pmtwigg]

I'll update once completed. Thanks for your help sir. You're a gentleman and a scholar 

[RDspaguy]

Hey! Gentleman AND scholar. I think that's a promotion for you, huh @CanadianSpaTech? Gold star buddy!⭐

[Pmtwigg]

Installed a new heater assembly. The old one was trashed. Everything is up and running. Back to normal. Thank you my Canadian friend