Hot Tub Motherboard heater plug fried

massimofinance

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Hi all, hope you guys can help me. One of the pumps on my Hot tub started to leak. Bought new seals, was going to take it out and replace them. When I went into the mother board enclosed box to unplug that pump, I noticed that the plug from the heater is fried. I drew an arrow pointing to the fried plug. It will not come off the motherboard. It was dry in there, so I am not sure what happened. Lately, the hot tub hasnt been heating all the way to 100, I thought it might have been the leaking pump. Question, is the motherboard now needing to be replaced? Will the heater need to be replaced as well? Any reason to now just try to fix the plug? a new motherboard is $$$. Thanks!
 

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alldodge

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Hi all, hope you guys can help me. One of the pumps on my Hot tub started to leak. Bought new seals, was going to take it out and replace them. When I went into the mother board enclosed box to unplug that pump, I noticed that the plug from the heater is fried. I drew an arrow pointing to the fried plug. It will not come off the motherboard. It was dry in there, so I am not sure what happened. Lately, the hot tub hasnt been heating all the way to 100, I thought it might have been the leaking pump. Question, is the motherboard now needing to be replaced? Will the heater need to be replaced as well? Any reason to now just try to fix the plug? a new motherboard is $$$. Thanks!

You had a bad connection which caused heat at the connector. Part of the connector has probably melted to the pins. I would suggest removing the board so you can get at the pins better. If you need more room, cut the wires at the connector so you can work on it at a bench. If all else fails you can solder the wires right to the board pins or surface.
 

gm280

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It sure did get hot, that's for certain. I would check the manufacture of the board and contact them for a new connector or see if you can get a replacement for it. Then cut back the charred wires until you get to good shiny wires again and replace the connector at that point. However, unless you can verify that the connector was corroded, there is some other reason that plug got so hot. And unless you can find that cause, it could happen again shortly after simply replacing the charred parts. I would also check the solder side to see if there is anything else charred on that side of the PC board. The actual charred plug seriously doesn't look that unique to replace. But make sure the jack is okay too... If you are familiar with electronics, do some ohming out of other parts to verify everything else is okay. I don't see a huge problem myself, but that's what I use to do was repair and replace circuits... Good luck!
 

Scott Danforth

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I would just replace the whole pump. part of what happens is the motors start to go about the same time they start to leak. not sure if the cheap motor bearings go first taking out the pump, or the cheap pump bearings and seals go first taking out the motor. repairing hot tub pump/motors is more costly than buying new. on-line, most pumps can be had in the under $300 range

regarding the mother board, it looks like a bad connection or a high current draw (posible failing pump?) and a marginal connection caused a bit of heat if you still have a good board, then simply get another plug (Moeler, digikey, etc). if not, get another heater unit with mother board.
 
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hungupthespikes

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Some really good info for you already posted. (+1) Pull the board and take a good look at both sides...most likely it's fine, just needs some TLC.
You said it was the heater plug so I'd take a hard look at the heater. With a leak and the heater not getting the water up to temp... it sounds like there is a problem with the heater. Could be shot or just a lot of crud causing the problem.

Anything that reduces the water flow through the heater would cause the heater to pull hard and never reaching the set temps, resulting in the plug melt.

good luck
huts
 

massimofinance

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Guys, thanks a TON for the very helpful advice (and sorry I called it a motherboard, it is a power pack, my bad). Anyway, the picture attached shows the power pack once I removedl it for Bench work, the plug is shot, but the socket on the board seems OK- just a bit dark and crusty. I will remove the board from the box and look at the back. Does anyone suggest I just replace the socket? If so, can you tell me where I find instructions on how to do that? I guess just solder it on? Also, as far as the plug goes, I have never replaced one of these, I assume you just crimp the leads on and insert into the white plastic plug holder- where is a good place to buy the leads and plug?

As for the reason this happened, might it have been the leak? the heater is clean as a whistle.

As for the repair or replace the pump, its been leaking for months now I think- does that mean you all suggest I just replace it?

Thanks!!!
 

thumpar

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I had a hot tub were the blower pump wouldn't work. This was a digital style tub. The brushes in the pump went bad and caused a shorts that fried the transistor on the board. I found new brushes and a transistor for about $10 and fixed it. No shop in town would work on the pump. If the connector got that hot you many have a blown component on the board from the current draw. They are not that complicated to work on if you have any electronics skills. Make sure to take lots of pictures as you take things apart.
 

massimofinance

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Thumpar, thanks, I will inspect all the transistors. How will I know if one went bad?
 

alldodge

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One of my pumps started leaking a few years back and all I did was replace the dripless seal. Was real easy and only took about an hour.

Just for clarity I'm calling the plug the thing with the wires on it, and the socket is on the circuit board.
As for the plug and socket. it would probably be easier to remove the plug and cut the wires off. Then solder the wires directly to the socket contacts on the board. There are electrical supply houses which we might find the parts

What kind of hot tub is this? model and manufacture?
 

levittownnick

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You had a bad connection which caused heat at the connector. Part of the connector has probably melted to the pins. I would suggest removing the board so you can get at the pins better. If you need more room, cut the wires at the connector so you can work on it at a bench. If all else fails you can solder the wires right to the board pins or surface.


I think AllDodge is right-on with the bad connection. I would follow his suggestions.

Good luck,
Nick
 

massimofinance

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thanks, this is a Laguna Bays X-6, two 6 HP pumps, 6 person tub, has Ozone. weird it went bad, its only two years old!

AllDodge, that sounds good, I will solder the heater wires directly to the board. Any advice on how to remove the socket from the board? is it connected in the back somehow? seems on there pretty good. Thanks.
 

alldodge

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thanks, this is a Laguna Bays X-6, two 6 HP pumps, 6 person tub, has Ozone. weird it went bad, its only two years old!

AllDodge, that sounds good, I will solder the heater wires directly to the board. Any advice on how to remove the socket from the board? is it connected in the back somehow? seems on there pretty good. Thanks.

Don't remove the socket unless you have to. Try to remove the plug off the socket, maybe with a drimal tool or similar. Then solder the wires to the socket if we cannot find a plug. My guess is with some more info we should be able to find a plug which may work.
 

massimofinance

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Thanks AllDodge. I plan on taking a dremel to the plug socket and taking away the plastic surrounding the plugs. Then, I will be soldering (ordered a cordless butane soldering iron today) the wires directly to the PCB. FYI, this forum rocks...
 

alldodge

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Thanks AllDodge. I plan on taking a dremel to the plug socket and taking away the plastic surrounding the plugs. Then, I will be soldering (ordered a cordless butane soldering iron today) the wires directly to the PCB. FYI, this forum rocks...

I hope it works out, but there is an issue with butane soldering. The flame will heat up the area real fast which is good, the bad is you need rosin on the metal to get solder to flow correctly. Don't use plumbers solder, use electrical solder. If you can find some real old electrical solder with a better core that would be even better. The good ole electrical solder I use to use when soldering weapon systems for the Navy is no longer made. Best you can get is 60/40
http://www.amazon.com/Electronic-Solder-050-lb-Spool/dp/B0002KR9F2
 

massimofinance

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SO, just following up- I dremeled the burnt plastic socket away and took the board out- if you look at the heater plug contacts on the back of the board, they are a bit brown- the plug ends on the front of the board are fine- what do you guys think? is it worth soldering the cable to the plug ends or does that browning on the back mean something bad? Thanks...
 

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thumpar

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If it was me I would remove both male and female contacts and replace. They shouldn't be hard to find at digikey or mouser.
 

ondarvr

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Hi all, hope you guys can help me. One of the pumps on my Hot tub started to leak. Bought new seals, was going to take it out and replace them. When I went into the mother board enclosed box to unplug that pump, I noticed that the plug from the heater is fried. I drew an arrow pointing to the fried plug. It will not come off the motherboard. It was dry in there, so I am not sure what happened. Lately, the hot tub hasnt been heating all the way to 100, I thought it might have been the leaking pump. Question, is the motherboard now needing to be replaced? Will the heater need to be replaced as well? Any reason to now just try to fix the plug? a new motherboard is $$$. Thanks!

If the wires go to the heater then the pump leak shouldn't have any effect on it. With a leaking seal you wouldn't be able to detect a difference in flow through the system unless the seal fell out.

Are these the only wires going to the heater? There are several safety switches between the board and the heater element and they should go to a contactor that supplies power to the heater, the power shouldn't come directly from the board. There should be a high limit, pressure sensor and/or flow sensor that will interrupt the power if they sense the wrong conditions.

Depending on the amp draw of the entire spa and the supply to it, the heater may switch to a lower amp draw when both pumps are running.

I will replace pump seals, they're cheap and easy to work on, I'm less likely to replace bearings unless it's on my own pump. The pump motors don't tend to last much longer than the first set of bearings, and the labor involved doesn't make the cost to the customer worth the risk of it only lasting a short time longer, so I normally just switch out the motor. Other than the seal there's not much in the pump itself to wear out, so the wet end is normally reused unless they want an upgrade.
 
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